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The Ventura Gem & Mineral Society, Inc. (VGMS)
Rockhound Rambling
July 2007.
Rockhound Rambling Photo of the Month.
This month's photo is by Mary Polacek.
Description: African Tiger Iron.
A banded mineral composed of tiger eye, red jasper and hematite. It is said to stimulate vitality and enhance the immune systems. It strengthens force of will and courage and can be utilized as a protective shield.
Rambling Picture of the Month is photographed by a VGMS Member. Subject may be a specimen in their own collection or a rock, mineral, gem or lapidary creation of others, accompanied with documentation of subject origin. Selection is at the discretion of the editor. Submit candidate photos to vgms_editor@roadrunner.com.
Permission is granted to quote any item, if proper credit is given. Exchange Editors: email to vgms_editor@roadrunner.com or mail to 3063 Bayshore Avenue, Ventura, CA 93001-4125.
For the record, any unsigned articles are by the Editor.
Table of Contents.
PRESIDENT'S MESSAGE.
It's with mixed emotions that I must announce the death of a founding member of our club, Ray Meisenheimer. I say mixed emotions because we're all sad to no longer have Ray to brighten our meetings and our condolences go out to Florence for her loss. But, even though I'm sad, I can't help smiling every time I picture his face in my mind. He always had some sly joke he was ready to spring on you, and was always there with advice or help if you needed it. I have no doubt he's already telling St. Peter how to run things up there. He touched the lives of literally thousands of people through his outreach to schools with his Earth Science talks, and with his many other charitable activities outside of our club. Ray will be sorely missed and fondly remembered.
Ed Clark, President.
Webmaster's Contribution: Go to the following link to see the article that appeared at the top of our home page following Ray's death - Ray's Link. (Close the new window to return here.)
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Table of Contents.
WORDS TO LIVE BY.
Blessed are those who can give without remembering, and take without forgetting.
When a man is wrapped up in himself, he makes a pretty small package.
Nothing is impossible. Some things are just less likely than others.
A good listener is just a good talker with a sore throat.
Collected by Wayne Ehlers.
Table of Contents.
UPCOMING VGMS EVENTS.
Regular Meeting - Wednesday, July 25, 7:30 pm, The Lexington, Ventura.
Board Meeting - Thursday, August 2, 7:30 pm, The Lexington, Ventura.
Bulletin Article Deadline - Sunday, August 5, email to: vgms_editor@roadrunner.com.
Workshop - Saturday, August 18, 9 am To Noon, Museum.
If omitted, time, location or address can be found on the VGMS Info Page. (Close the new window to return here.)
Table of Contents.
BIRTHDAYS.
Sharon Cunningham - July 07,
Nancy Brace-Thompson - July 27,
Ronald Chegwidden - July 29.
Ed Clark - August 12,
Marie Haake - August 14,
Sunny Cross - August 19,
Karen Foster - August 24,
Shirley Bromser - August 25,
Mel Hixson - August 26,
Craig Andrews - August 31.
July Birthstones:
Modern: ruby.
Ancient traditional:
Hebrew: onyx,
Roman: onyx,
Arabic: carnelian,
Hindu: sapphire,
Polish: ruby,
Russian: ruby,
Guardian angel: verchiel,
His talismanic stone: sapphire.
Zodiac gemstones:
cancer: emerald.
leo: onyx.
July Flower:
Common Name: Larkspur,
Botanical Name: Delphinium ajacis,
Color: Pink,
Meaning: Fickleness.
Image Source: Hubert J Steed, 30-Jun-2005.
Table of Contents.
HOSPITALITY.
Twenty-five members attended the June regular meeting.
Jean and Ron Wise, Valli Davis and perhaps others for whom I do not have names brought refreshments for all. Yummy! Thank you.
Following are the volunteers for the remainder of 2007. If anyone would like to volunteer for any of the open months, please contact Sharon Cunningham, and we thank you in advance.
July - Sharon & Mel Hixson,
August - OPEN,
September - OPEN,
October - Stephenson family,
November - Pumpkin potluck,
December - Holiday potluck.
Thank you to those who have already signed up. Contact Sharon Cunningham, 649-3579, if you are willing to supply refreshments for one of the open months in the schedule above.
Table of Contents.
MEMBERSHIP.
Club Yellow Pages: Share Your Info Today!
Our thanks to everyone who has returned the postcards for our "Club Yellow Pages" indicating your specific areas of interest within our hobby. With 32 responses thus far, we've heard from about half the membership. Again, many thanks to all who have responded! We plan to print and distribute the Club Yellow Pages at the August meeting. (If you won't be there, don't worry. We'll also mail out copies.) As a reminder, the Club Yellow Pages will list specific interests of club members to make it easier for members (especially new members) to connect with fellow members who share a common interest. This also might help each of us explore areas of potential interest. For example, if you've always been tempted to try silversmithing but don't know the first thing about it, the Club Yellow Pages might guide you to someone already experienced in silversmithing who might be willing to give you a demo and pointers.
If you haven't yet filled out and returned your postcard, please do so today! Alternatively, you can call 805-659-3577 or email jbraceth@roadrunner.com to let us know which of the following categories are of special interest to you:
1) Crystal, mineral & rock collecting;
2) Carving & sculpture;
3) Education (kids' activities, school visits);
4) Faceting;
5) Fluorescent minerals;
6) Fossils & paleontology;
7) Field trips;
8) Lapidary arts & jewelry making;
9) Meteorites, tektites & astronomy;
10) Mining history & artifacts;
11) Micromounts & thumbnail specimens;
12) Photography;
13) Silversmithing;
14) Other (please specify).
For each area of interest, please indicate whether you consider yourself a "novice" or an "expert" and provide any further elaboration you'd like to include. This is our last call before we print the yellow pages, so don't delay - call or email today!
Jim & Nancy Brace-Thompson, Membership Chairs.
Directory Update:
Please update Nancy and Jim Brace-Thompson's e-mail address: jbraceth@roadrunner.com.
Are there any Adelphia customers who have converted their accounts to Roadrunner? We would like to hear from you!
Table of Contents.
PROGRAM REVIEW.
June Program: VGMS Book Club and Reports from the California (Lancaster) and National Gem Federation (Roswell) Conventions.
June's program wound up being a real page turner. Several members volunteered to share their recent acquisitions, including Jim Brace-Thompson, Mel Hixson, Ron Wise, Wayne Ehlers, and myself. (Please forgive me if I missed somebody or left out material, as I wasn't taking notes, and my memory a month later is a little faulty.)
I started the program by sharing some material we have in our club library. This included Desert Magazines from the 1950's, a well-written California Gem Guide, and a photo album chronicling the opening of our museum/shop many years ago. I also shared a recently published GPS guide to the Hauser beds.
Ron shared a book from the Roadside Geology series which he highly recommends.
Wayne let the club know that the recent Rock and Gem magazine contains an article on rhodochrosite, which was the subject of our movie in May.
Jim Brace-Thompson shared a compact yet informative and colorful book on agates. He also brought a book on Australian Agates that evidently comes with its own Australian accent when you hold it.
Mel brought several books of which I distinctly remember two. One, a book by June Zeitner, he does not recommend as it contains information previously published in the Lapidary Journal. The other text was a gargantuan brick of a book about agates. This monstrosity was filled with page after page of gorgeous photography. The book, Agates by Johann Zenz, has 650 pages and over 2,000 photographs. Like the agate book brought by Jim, Zenz's book lacks depth for American sites, but covers the rest of the world, especially Europe, extremely well.
The program went smoothly, and I want to thank everyone who participated. I hope people saw some things that they may like to add to their library.
Lowell Foster.
Table of Contents.
PROGRAM SCHEDULE.
July Program: History and Updates on our State Gemstone, Benitoite.
For our July program, Jim Brace-Thompson will talk about our official state gemstone, benitoite. With slides, a brief video, and samples, he'll tell us about benitoite as a mineral and gemstone and overview the history of mining activities in the Clear Creek Mining District. He'll also provide a handout with a timeline of significant events involving benitoite since it was first discovered 101 years ago. (One Los Angeles lapidary at the time dismissed it as "volcanic glass of no value"; cut specimens now go for as much as $1,600 per carat!)
The handout will include a template on cardstock so that you can cut out and make your own benitoite model - it's the only known mineral that takes the ditrigonal-dipyramidal form within the hexagonal system. If you don't know what that means, don't worry. Jim doesn't either, but it's apparently very unique!
The benitoite mine passed through several different hands over the course of the last century, but one thing always stayed the same: it was closed to prospecting by anyone except the owners, a policy that was strictly enforced. The good news is that as of 2005 the mine lease has been purchased by Dave Schreiner of Coalinga for the express purpose of opening it up to all rockhounds as a fee dig. Come to the meeting for details!
While Jim will be bringing some examples of both faceted and specimen benitoite, we'd like to encourage anyone else who has specimens to bring them along to show everyone alongside Jim's. See you at the July meeting!
Jim Brace-Thompson.
Table of Contents.
MEETING MINUTES.
Minutes of the VGMS Regular Monthly Meeting,
Wednesday, June 27, 2007:
The regular monthly meeting of the Ventura Gem & Mineral Society was called to order by Ed Clark at 7:30 pm on Wednesday, June 27, 2007 at The Lexington, Ventura, California. The May membership meeting and the June board meeting minutes were corrected and then m/s/c as shown in the bulletin.
Ed Clark welcomed guests. Ed also announced the sad news that Ray Meisenheimer has been diagnosed with liver cancer.
Lowell Foster: Jim Brace-Thompson will be presenting his program on benitoite in July.
Ron Wise: The Conejo club will lead a trip to the Kanan Road area on July 28.
Mary Polacek: Articles to the bulletin will be required by the first Sunday after each board meeting. Any and all articles and photos will be greatly appreciated. More letters to Mel, from children receiving his polished stones, will be highlighted in an upcoming bulletin.
Greg Davis: The Lexington was contacted and we were given permission to hold monthly board meetings in the Piccadilly room until we find something else. No word yet from Help of Ojai on space availability for our museum.
Jim Brace-Thompson: The idea of yellow pages for members has met great success with most returning the forms. It would be a method of listing one's expertise or favorite aspect of the hobby which you would then help new members with. The final form should be ready for distribution in August.
Richard Bromser presented the treasurer's report. He also had signup sheets for volunteer duty at the County Fair.
Wayne Ehlers mentioned to members that the same rhodochrosite crystals seen in our video last month were also featured in the latest Rock & Gem magazine. Wayne also offered to present a program on agates during a monthly meeting this year. Lowell will check his calendar.
Abe Barshai: Plans are being made for the 2008 show at the fairgrounds. Unless members offer to man the Country Store, it will have to be eliminated this time.
Ed Clark announced that at the CFMS show in Palmdale, Shirley Layton won 1st place as Editor in the CFMS bulletin editor competition and 5th place in AFMS competition for Best Large Bulletin. Lowell took 2nd in CFMS and 10th in AFMS for Best Original Adult Article. Ed, himself, took 1st in cabbing, a 1st in fluorescent mineral display and Best of Show in Lapidary Overall. Congratulations to all!
Lowell next asked members to share CFMS show finds, materials and books pertaining to our hobby. Ron Wise, Mel Hixson and Jim Brace-Thompson, along with Lowell, offered info and shared some excellent books on agates.
Refreshments were provided by Ron & Jean Wise.
The next board meeting will be held on July 5th at the Lexington. The next monthly membership meeting will be on July 25.
There being no further business, Ed adjourned the meeting at 8:55 pm.
Respectfully submitted,
Greg Davis,
Recording Secretary.
Minutes of the VGMS Board Meeting,
Thursday, July 5, 2007:
The regular board meeting of the VGMS was called to order by Ed Clark at 7:30 pm on Thursday, July 5, 2007, at the Lexington in Ventura.
Present: Ed Clark, Shirley Layton, Ron Wise, Jim & Nancy Brace-Thompson and Greg Davis.
Ed Clark: Ray Meisenheimer's recent passing was so sudden and will be a very large loss to many people and service organizations. Many friends from all over California are reportedly attending Friday's service.
Old Business:
Ed Clark: There not being a forum, no club business was voted on.
Greg Davis: Members still need to contact myself or Ron prior to going to the museum/workshop to confirm its availability. There will be a workshop July 21st.
New Business:
Greg Davis: Lisa Meeker of Help of Ojai has been emailed regarding status on our request. Any answer will be forwarded to club and/or board members.
Jim Brace-Thompson: The yellow pages showing members' lapidary specialties were previewed and the finished version will be ready in August. Jim has also offered to fill in for Florence as our Federation representative. A membership application for Aegus Sweet is still pending. Jim will call the prospective member.
Shirley Layton can still be emailed with changes and additions to our web site.
Ron Wise: No field trips are planned for July and the upcoming Ventura County Fair will take most everyone's time through August. Ron has suggested the club form a work party as soon as possible and relocate show material to the alternate storage area that has been offered. Greg will contact Steve Mulqueen and reconfirm the facility's availability. Nancy Brace-Thompson will organize a phone tree to contact members as to when, possibly July 14th.
Ed Clark mentioned that he will be out of town from July 21st through August 27 and so will be missing two meetings.
The next general meeting will be on July 25, 2007, at the Lexington in Ventura and the next board meeting will also be held at the Lexington on August 2nd.
There being no further business, the meeting was adjourned at 8:05 pm.
Respectfully submitted,
Greg Davis,
Recording Secretary.
Table of Contents.
CHIPS AND BOULDERS.
To Florence.
I have been struggling with this issue. It is difficult to express my feelings. I am a relatively new member in this club; unable to draw upon that vast well of memory of the many, many years of Ray's membership in the VGMS.
It was evident from my first VGMS meeting that Ray was a dynamo upon which the club turned. To be honest, at first, Ray scared me. I was ignorant and he was, well, just so BIG, in stature as well as reputation. My admiration of him grew and I soon warmed to the shine, viewed the glint from this true GEM of a man. Ray and Florence, how ultra GIVING. It is a rare VGMS member that does not have a piece of Meisenheimer magic in their personal collection, thanks to their long, long tradition of SHARING.
Mary Polacek.
Last Call for Country Store.
It makes me sad to think our Country Store may be done away with, because no one will volunteer to take it on. We have many repeat customers every year (including many exhibitors) who look forward to the store. It is fun and not as difficult as one may think. We are going to be around for longer than anticipated, probably through September, and I will be happy to work with anyone who would like the challenge. It is really fun. The hardest work is the setting up on Thursday and Friday. It's best to have a few pre-show pricing sessions and then Sunday night packing up which usually has several helpers and goes fast. We were real new members when I took it on and I have enjoyed every year of it!! You meet wonderful people. Think about it!
Shirley Layton.
Ventura County Fair 2007.
The 2007 Ventura County Fair will soon be here: August 1 through August 12. The theme for this year is "An Old Fashioned Fair".
Volunteers are needed, for four or more hours, to assist with set up of the Gem and Mineral building, beginning on Thursday, July 5. Lunch will be provided for the volunteers.
Entry dates for Hobbies and Collections: Friday, July 20; Saturday, July 21; and Sunday, July 22.
Entry dates for Gem and Mineral: Friday, July 27; Saturday, July 28; and Sunday, July 29.
We need people to help to accept exhibitor entries on all of these dates. If you can commit to four hours or more - that would be great!
Judging will be done on two Tuesdays, July 24 and July 31. We need people to clerk for each judge on these dates. This will require a commitment of four or more hours on either date.
This is a good time to start planning your entries. Do you have your own case? Will you need to use one or more of the fair cases? Do you have single items to enter?
Please call Richard Bromser if you can help on any of the above dates, if you need more information, or to reserve a case. Just leave a message, if I don't answer. I'll be sure to return your call.
Richard Bromser.
Note from Shirley.
This seems sort of odd to be sending something to the editor to be put in the bulletin! I'm not sure if you all are aware that the "Rockhound Rambling" won first place in the 2007 CFMS Bulletin Editor Contest in the large bulletin class and 5th place in the 2007 AFMS Bulletin Editor Contest in the large bulletin class. That was kind of a nice retirement surprise! Jim and I just want to thank all of you for your contributions, help and encouragement in the 10 years we did it. It wouldn't have been a winner without your help and input. Thank you!
We would also like to congratulate Lowell Foster on his 2nd place in the Original Adult Articles Class in the 2007 CFMS Bulletin Editors Contest and 10th place in the AFMS Contest, for his Virtual Field Trip articles. It was hard to pick one as they are all fun. Keep up the good work Lowell and Thank You!
We are really lucky to have Mary step in and give us a wonderful bulletin each month. It makes me feel good to know it is in good hands! I predict she will be a winner in the New Editor contest! All of you need to give her good material and your input. It really does make her job more fun and also the bulletin more interesting when there is member contribution. One of the judge's comments was "Sounds like a fun, active group of people who care about one another and truly enjoy and benefit from the club." This was from the input you gave.
My last thoughts are to Florence Meisenheimer and her family. We attended Ray's services and some fun stories were shared. Ray would have enjoyed it! Ray was a great educator and never met a stranger. He will be missed and remembered with a smile.
[For those who may have missed Ray's obituary, it has been posted
in it's entirety on the VGMS website.]
Shirley Layton, "Retired or Tired Editor".
VGMS Workshop is open the third Saturday of each month from 9:00 am to noon unless otherwise notified. Shop Supervisors are Ron Wise (805) 647-4393 and Greg Davis (805) 647-9214. If you plan to attend, call ahead to make sure the museum will be open. A big thank you to Ron and Greg for the opportunity they give the rest of us. The workshop is there for your use; take advantage of it.
Tumbling Grit is still available. Contact any board member to arrange for pick up or come to a workshop Saturday at the museum.
What's in a name?
Uvarovite - after Count S. S. Uvarov, president of the Academy of St. Petersburg.
Aragonite - after Aragon, a former kingdom in Spain.
Turquoise - after Turkey, from whence it was brought to Europe.
By Ed Clark From Gems Minerals Crystals and Ores by Richard M. Pearl..
Table of Contents.
SUPPORT AND PRACTICE
THE AFMS CODE OF ETHICS.
Jury Duty Scam.
This has been verified by the FBI (their link is also included below). Please pass this on to everyone in your email address book. It is spreading fast so be prepared should you get this call.
Most of us take summons for jury duty seriously, but enough people skip out on their civic duty, that a new and ominous kind of scam has surfaced. The caller claims to be a jury coordinator. If you protest that you never received a summons for jury duty, the scammer asks you for your Social Security number and date of birth so he or she can verify the information and cancel the arrest warrant. Give out any of this information and bingo; your identity just got stolen.
The scam has been reported so far in 11 states, including Oklahoma, Illinois, and Colorado. This (scam) is particularly insidious because they use intimidation over the phone to try to bully people into giving information by pretending they're with the court system. The FBI and the federal court system have issued nationwide alerts on their web sites, warning consumers about the fraud.
Check it out here. (You can copy these links, one at a time, and paste them into your browser's address line to see if they're still good.):
http://www.snopes.com/crime/fraud/juryduty.asp,
http://www.fbi.gov/page2/june06/jury_scams060206.htm.
Table of Contents.
FREE ONLINE GEMOLOGY COURSE.
If you're interested in learning about gemology from a scientific (rather than a commercial or artistic) viewpoint, then you might enjoy this web site. Included there is a series of lessons developed by Barbara Smigel, Ph.D., GG, and Emeritus Professor at the Community College of Southern Nevada. You don't need to register to use the materials contained on the site, however you can opt to register and take the full distance learning, on-line course for college credit. Web Lectures include the following lessons:
Lesson 1: Basic Terms,
Lesson 2: Naming and Measuring Gems,
Lesson 3: Physical Properties of Gems,
Lesson 4: Optical Properties of Gems,
Lesson 5: Magnification and What it Reveals,
Lesson 6: Optical Phenomena in Gemstones,
Lesson 7: Gem Fashioning,
Lesson 8: Gem Enhancement,
Lesson 9: Synthetics and Simulants,
Lesson 10: Gem Formation.
Also included on the site are Web Essays - one-topic, pictorial essays that enrich the web lectures for each lesson and include information on specific rocks and minerals. You can follow a link to "Ask the Teacher" specific questions and actually receive an answer in response. There's also an audio pronunciation guide, an A-Z Survey of Gemstones downloadable as a Power Point presentation, and suggested text books and reading assignments if you're interested in learning more. Simply visit http://www.bwsmigel.info/. Check it out!
From Salinas Valley Rock and Gem Club Newsletter, July-August 2007.
Table of Contents.
Seven Wonders Vote.
The New 7 Wonders of the World, as announced in random order at the Official Declaration Ceremony on July 7, 2007, are:
The Great Wall of China;
Petra, Jordan;
Chichn Itz, Mexico;
The Statue of Christ Redeemer, Brazil;
The Colosseum, Rome;
Machu Picchu, Peru;
The Taj Mahal, India.
More than 100 million votes were cast worldwide. The New 7 Wonders are all equal - there is no rank among the list. 7 Wonders were chosen because the original list of Ancient Wonders, drawn up more than 2,000 years ago, contained 7 and because 7 has been shown time and time again to be the number of things that the average person can remember. The Pyramids of Giza also were honored by the New7Wonders project as the only remaining of the 7 Ancient Wonders of the World.
Table of Contents.
FIELD TRIPS ARE FUN.
Cerro Gordo Mine by Andrew Turner via LA-ROCKS posting Thursday, June 28, 2007, 12:52 pm.
On Saturday, June 23, my girlfriend and I headed to Lone Pine to join the Lone Pine Gem and Mineral Club and CFMS on their yearly trip to Cerro Gordo. This was our second trip here as we had gone two years ago as well.
On the way to Lone Pine, we stopped near Little Lake in order to collect some obsidian. However, we were unable to collect due to the site now being part of the China Lake naval weapons station. We decided to drive down the power line road to see if anything was there and stumbled across an old cinder mining area. We noticed several small pits and holes on the hill and went to see what people had been collecting. It turns out that there were beautiful yellow crystobalite crystals and botroydial masses in the scoria vugs. They were easy to find and very attractive. The crystobalite had the color of yellow adamite. We collected for about a half hour and headed to Lone Pine.
After spending the afternoon in Lone Pine (including at the great rock shop there--lots of local stuff), we camped at Diaz Lake. We met our 60+ new best friends at 8 am on Sunday and headed up the "fun" road to Cerro Gordo (8,000 foot elevation). I hadn't missed that road at all, and driving in a cloud of dust created by all the other cars is an experience. After a brief introduction, we began collecting on the dumps.
The first place I visited was a small dump that contained some interesting secondary copper minerals. I collected some nice azurite pieces (including small crystals), small balls of malachite, chrysocolla, rosasite? and other copper minerals. Some galena and ore minerals were also found here. I then headed to the largest and steepest dump in search of the elusive blue smithsonite. I had been very lucky on a previous trip when I found several nice thumbnail size pieces of this mineral. Unfortunately, I was never able to find the same vein as before. After a few hours of digging into the pile, I managed to only find one good piece. I can't complain as this piece was a good 1.5 inches long and covered in blue smithsonite. The wind picked up and all of us digging in the piles got covered in dust. No one appeared to get really lucky with the smithsonite this year.
After digging several hours, my girlfriend informed me that she had located another pile of great copper minerals. It was a pile I had been familiar with from a previous trip but was unable to locate it earlier. She showed me what she and others digging on the pile had found. Although most people collected large chunks of massive chrysocolla and malachite (a few pieces were fantastic), I was after the more crystalline material. I ended up finding some great pieces of botroydial chrysocolla and malachite, azurite, and probably rosasite, brochantite, etc. I also found several spectacular pieces of baby blue aurichalcite. This is some of the best aurichalcite I've seen outside of Mapimi, Mexico. The crystal clusters were in large masses and often on a very dark matrix, making the contrast very attractive. The largest piece I found was about 4x2 inches and covered with dozens of clusters.
The best piece I found I didn't even realize until I got home. I thought I had collected a nice 3-inch piece covered in bright blue azurite (a fairly rare find in that quantity) on an all white matrix. However, after washing it and checking it under a loupe, I realized it was actually a great piece of linarite. There were even elongated tabular micro crystals on the backside. The color was distinctly different from the darker blue azurite from here. I know linarite has been found here (there is plenty of lead and copper), but this piece is one of the largest and best I have seen. Probable caledonite is also on the piece, but hard to confirm.
After digging for another hour or so looking for smithsonite and only finding a very mediocre piece, we finally headed back home to Victorville around 3 pm.
A few thoughts about the trip:
-the Lone Pine Club did another outstanding job at organizing and coordinating the trip. Due to it being a CFMS trip this year, there were a lot of people, but no problems at all.
-while most people look intently for the famous smithsonite, I've noticed that many people tend to overlook the great copper minerals, as well as the nice quartz and ore minerals (galena) from here. I've seen several people get discouraged as the smithsonite is hard to find and often requires a lot of work to locate. I ended up being very happy despite not finding some of the quality smithsonite that others found.
-do not try to climb all over the dumps with a torn meniscus in your knee. I learned this the hard way and was in a lot of pain afterward. I should have just dug at the base of the piles, saving myself a lot of heartache and probably being just as successful.
FIELD TRIP SCHEDULE 2007.
Tentative Schedule - As of 6/15/2007.*
| MONTH: | ||||
| Date(s), | Event/Location, | Sponsor/Leader, | Other Information. | |
| July: | ||||
| 28, | Kanan Road Cut, | Robert Sankovich, Mike Miller. |
||
| 28, | Oxnard Public Library, | David Lynch. | ||
| LEADERS: | ||||
| Bret Johnson, | 805-984-8872, bj9709@yahoo.com, |
Oxnard G&M (OGMS). | ||
| Mike Miller, | 805-498-9586, | Conejo G&M (CGMS). | ||
| Robert Sankovich, | 805-494-7734, rmsorca@adelphia.net, |
Conejo G&M (CGMS). | ||
| Ron Wise, | 805-647-4393, clintwise@hotmail.com, |
Ventura G&M (VGMS). | ||
*Please call field trip leader to confirm schedule in the event of a change to published dates/times.
JULY 28, Saturday, 9 am-NOON: KANAN ROAD CUT.
Contact:
Robert Sankovich, 805-494-7734, rmsorca@adelphia.net.
Mike Miller, 805-498-9586, rockfmdr@aol.com.
Please let us know if you are going to go on the field trip.
This is a different site than January's Kanan Road field trip. We will be collecting along Kanan Road, and up on the road cuts on Kanan Rd. It's a short walk from where we will be parking. Minerals can be found along the base of the hill, or up on the road cut, which will require digging.
If you do go, please be careful as we will be close to Kanan Road, and there is traffic. We will be collecting on both sides of the road, so be careful crossing the road. This might not be a good field trip for small kids. We will be collecting Agate, Marcicite, Onyx, Drusy Quartz. Summer is upon on, so we will be collecting earlier in the day and stopping before it gets too hot.
Directions:
From Thousand Oaks head South on 101, get off on Kanan Road in Agoura. Turn Right (South). Go 3.9 miles to a pullout on the right (west) side of the road. There is a orange sign with "Single Lane Ahead, 35 mph" at the pullout area. The parking area is 1.1 mile past Troutdale. If you've reached the tunnel on Kanan Road, you've gone too far.
We will meet at the site. There will be a short briefing of the site. Please remember to sign the release form to participate in the field trip. This is an easy access, short walk 20 yards or so, from where we will be parking.
GPS: N 34 06.964; W 118 48.025.
What to Bring:
Collecting bags, buckets, day pack, digging tools, rock pick, pry bar, eye protection, gloves, trowels, wide brimmed hat, sunglasses, sunscreen, sturdy shoes, drinking water, lunch or snacks.
JULY 28, 2-3:00 PM, OXNARD PUBLIC LIBRARY.
Dr. David K Lynch, an astronomer and planetary scientist, will present a lecture based on his book, Field Guide to the San Andreas Fault. His presentation will address topics such as: What is the San Andreas Fault; Can You Actually See and Touch It; What is the Geologic Future of California. Did you know that the San Andreas Fault is the most accessible plate boundary in the world? Dr. Lynch will show photographs of the actual fault and its attending landforms. His book, available for purchase, provides detailed maps. The program is FREE and refreshments are provided.
July 28 at 2:00 pm in Meeting Room B of the Oxnard Public Library, 251 South A Street, Oxnard. For further information call 385-7532.
Table of Contents.
HINTS AND TIPS.
Cutting Geodes in the right place can be tricky. Try rolling the geode on a flat floor several times and mark the up side each time. Then cut on a plane parallel with the floor. Crystal growth inside the geode is probably most developed at the top and bottom of its resting position.
Original source unknown from Choo-Choo Chatter, 3-4/04 via Rock Writings 09/04.
To open geodes, soak a string in kerosene, tie it around the geode. Burn the string, then plunge the geode in cold water. In many cases, this will crack the geode and a light tap with a hammer will finish the job.
Original source unknown from Breccia 06/98 via The Nugget 01/99.
Gold's worst enemy is chlorine. Continued exposure to chlorine in swimming pools, chlorinated cleaners, etc., can eventually cause it to weaken and break.
From World Gold Council via Drywasher's Gazette 01/99.
To recycle dirty oil from your trim saw, pour the used oil in a disposable container, e.g., a coffee can. Add hot water and stir. The hot water warms the oil and lowers its viscosity so that the trash can settle out more easily. Water, being denser than the oil, sinks to the bottom. The dirt that suspended in the oil, settles out and sinks to the bottom of the water, leaving clean oil on top. Put the whole works in the freezer. The water will freeze. Pour off the clean oil and throw away the dirt and water.
Dick Rathjen, Backbender's Gazette, 06/96 via Rocky Review 01/99.
To judge the size of a jeweler's saw blade to use, figure two teeth should touch the material being cut. Lubricate the blade before using (beeswax is good).
Al Klein, AFMS Newsletter 10/98 via The Nugget 01/99.
Measuring Grit.
Most tumbling instructions tell you how much grit and polish to use per pound of rock, and is most often given in ounces. An easy way to arrive at ounces is to use a standard measuring spoon and level off with a knife.
| ONE OUNCE of: | Equivalent: | (ONE TABLESPOON = 3 TEASPOONS). |
| Course Grit, Medium Grit, Fine Grit, Polishing Powder, |
4 TEASPOONS. 4 TEASPOONS. 4 TEASPOONS. 8 TEASPOONS. |
|
| From The Agatizer via Del Air Bulletin 01/07. | ||
Bicarbonate of Soda is one of the most reliable aids for outings. It:
Takes the itch out of bites and stings.
Soothes the irritation caused by poison ivy, poison oak or nettles.
Relieves sunburn and windburn and is also effective for any burns.
Sweetens ice chests as well as stomachs.
Removes odors (such as onion, garlic and fish) from hands or preparation surfaces.
Loosens bug spatter from windshields.
Helps snuff out camp or car fires.
From Drywasher's Gazzette via The Rockhounder 02/99.
The club presents these hints and tips for informational purposes only and does not specifically endorse or profess first-hand use or experience with any or all. As always, be aware of your situation, knowledge level and comfort zone before attempting anything new. When in doubt, stop! Get help before you need it.
Keep a log in your shop. Document your techniques and inspirations. You will come up with a journal full of useful tips, and maybe even an educational article or two!! Email hints and tips to vgms_editor@roadrunner.com.
Let us hear about your good ideas!
Table of Contents.
EDUCATIONAL CORNER.
Definition of the Month.
Marine Terrace - An erosional and depositional feature formed by the action of the ocean surface on a land mass and the eventual change in elevation of the feature above or below sea level. Marine terraces are usually formed at the shoreline by the abrasive action of pounding surf and tidal surges, resulting in erosion, the deposition of beach and/or tidal sediment with marine organisms. With time, these geomorphic features may be submerged or uplifted beyond their original mean-tide sea level as a result of the slow movement of land masses.
In the Palos Verdes Peninsula of Los Angeles County, there are 13 major marine terraces exposed in the hills. They resemble a massive series of stair-steps reaching to the highest hill. Most of the terraces were formed during the Pleistocene epoch. The highest terrace represents the oldest feature of its type in that area, exposed at an elevation of over 1400' above sea level.
Source of Data: "A Day on the Palos Verdes Peninsula", a field guide written by Arthur R. Brown and John Cooper, Pacific Section, Society for Sedimentary Geology, 2006.
Written by Steve Mulqueen for the Ventura Gem & Mineral Society, July 2007. The "Definition of the Month" features words related to geology, paleontology, mining and desert history.
Illustration of the Month.
Dwarf Mammoth Fossil from Santa Rosa Island - An illustration of the in-place, excavated fossil remains of the almost complete skeleton of a dwarf mammoth found near Carrington Point on Santa Rosa Island. (The dwarf mammoth is also referred to as a pigmy mammoth). This discovery was made by Tom Rockwell in June of 1994. Rockwell, a geologist, was with a graduate student conducting field work to examine features of three elevated marine terraces on the island. This scientific research project was associated with the Geology Department at San Diego State University. When the fossil was found, only a small section of the vertebrae was exposed at the surface.
Shortly after the discovery, the fossil site was examined by Larry Agenbroad, a renowned paleontologist from Hot Springs, South Dakota. From this initial inspection, Agenbroad determined that the fossil bones definitely represented a dwarf mammoth and that the remains may be a complete skeleton. An excavation team was assembled and began work at the site in August 1994. The extraction of the bones revealed that approximately 90% of the remains were still in-place, in the exact position where the animal died. The remains were air-lifted by helicopter to a staging area at park headquarters on the island and later transferred by boat to Ventura.
The skeleton was transported to the museum laboratory at The Mammoth Site located in Hot Springs, South Dakota for cleaning, preparation, preservation, replication and for detailed examination. From this work, the species was determined to be an adult animal of the genus Mammuthus exilis and measures 5 1/2 feet tall at the shoulders. Carbon dating results indicated that the bones were 12,840 +/- 410 years old. A fiberglass replica of the skeletal remains, prepared in South Dakota, can be viewed at the headquarters of the Channel Island National Park in Ventura. The actual fossil bones are stored at the Santa Barbara Museum of Natural History.
This specimen is the best preserved example of the dwarf mammoth, thought to be a descendant of the larger Columbian mammoth. The species Mammuthus exilis evolved on a large island land-mass in the present-day Santa Barbara Channel during the last ice age, when sea levels were 300 feet lower than they are today. The Channel Islands in the area offshore of Ventura and Santa Barbara Counties represent remnants of this original island.
Illustration Source: From the geological field guide "Geology of Santa Rosa Island", written by John Woolley, Coast Geological Society, 1998.
Data Source: From the field guide listed above and from "Giant Island/Pigmy Mammoths: The Late Pleistocene Prehistory of Channel Islands National Park", written by Larry D. Agenbroad and Don P. Morris, written and published for the International Mammoth Conference, 1999, Rotterdam, Netherlands.
Text for this illustration was written by Steve Mulqueen for the Ventura Gem & Mineral Society, July 2007. The "Illustration of the Month" features a drawing, sketch, pen & ink rendering, engraving print or any form of art rediscovered in books, maps, manuscripts and many other sources related to geology, paleontology, mining and desert history. This illustration was chosen for its educational content by Steve Mulqueen.
Table of Contents.
LET'S BE SAFE OUT THERE.
We are entering the brutal months of summer. It is a good time to review two dangers of enjoying our hobby in the field: heat exhaustion and heatstroke. It is important to understand the difference between heat exhaustion and heat stroke. The first aid is different for each. There is a fine line between heat exposure (usually treatable) and heat stroke (potentially fatal). Err on the side of caution. Get professional help FAST if you are uncertain of presenting symptoms.
Heat transfer from the body occurs via the following 4 mechanisms:
1. Conduction is the transfer of heat via direct physical contact with a cooler object; it accounts for 2% of the body's heat loss.
2. Convection is the dissipation of heat from the body to the air and water vapor surrounding the body; it accounts for 10% of the body's heat loss. When air temperature exceeds body temperature, the body gains heat energy.
3. Radiation is the transfer of heat to the environment via electromagnetic waves; it accounts for most heat dissipation. As long as there is a temperature gradient between the body and the air, 65% of the body's heat is lost by radiation.
4. Evaporation is the transfer of heat by transformation of perspiration and saliva into a vapor; it accounts for 30% of the body's heat loss.
When air temperature exceeds 95°F, radiation of heat from the body ceases and evaporation becomes the only means of heat loss. Evaporation is maximally efficient in a dry environment. If humidity reaches 100%, evaporation of sweat is no longer possible and the body loses its ability to dissipate heat. I'll do the math for you ... you lose 75% of your body's capability to cool down. If you are hot and NOT sweating, BEWARE...this is a particularly dangerous sign.
Acclimatization to heat takes days to weeks and allows a person to safely be active at temperatures that would have previously been dangerous.
Thermal maximum is a measure of the magnitude and duration of heat that cells can encounter before they begin to denature proteins. Individuals may begin to sustain cellular damage anywhere from 45 minutes to 8 hours after exposure to core temperatures of 107.6°F.
Those rocks have been there for millennia; they'll wait for your safe return!
HEAT EXHAUSTION SYMPTOMS often resemble a viral illness and may be more dangerous than evident:
* Fatigue, weakness, dizziness or fainting;
* Nausea and vomiting;
* Headache, Muscle cramps and pain in muscle(s);
* Irritability;
* Hair standing on end;
* Blood pressure or pulse change when standing, abnormally rapid heart rate;
* Could appear pale, could have clammy skin;
* Could be sweating profusely, body temperature could be normal or high.
HEAT EXPOSURE TREATMENT:
* Get the person out of the sun.
* Have the person lie down.
* Loosen or remove clothing.
* Fan the person or apply cool water to the person's body to lower the temperature.
* Give the person electrolyte beverages, like Gatorade, or small sips of salt water.
* Do not give any drugs, alcohol or caffeine to the person.
* Watch the person closely. If the person's condition does not improve in a little while, call a doctor.
HEAT EXHAUSTION PREVENTION:
* Wear light, loose fitting clothes and a hat in the sun.
* Drink a lot of water (even if you don't feel thirsty).
HEAT STROKE SYMPTOMS:
* Body temperature at or over 105 degrees;
* Person probably isn't sweating much;
* Skin will be hot and red;
* May be dizzy or nauseous;
* Pulse may be rapid.
HEAT STROKE TREATMENT:
* Immediately call a doctor.
* Get the person out of the sun.
* Take off the person's outer clothing.
* Apply cool water or apply cold packs to the person's body to lower the temperature.
* If the person is conscious, provide small sips of salt water.
* Do not give any drugs, alcohol or caffeine to the person.
HEAT STROKE PREVENTION:
* Wear light, loose fitting clothes and a hat in the sun.
* Drink a lot of water (even if you don't feel thirsty).
* Take in a little more salt than usual with meals. This helps retain water.
Protect Your Noggin.
The average safety hard hat weighs 14 ounces. The average man's head weighs 14 pounds. An ounce of safety for every pound of head, provided the head protection works properly and is maintained. The skull; in normal circumstances protects the brain. When a possibility of injury from falling or flying objects exists, additional protection is required.
The force of a falling object can be calculated approximately by multiplying the weight of the object by the distance of its fall. For example, a 3.5 ounce washer falling 32 feet will generate a force of 7 foot pounds of impact. Should the washer strike an uncovered head, the force of the blow would be equivalent to 560 pounds. When a hard hat is worn, the force transmitted to the back and spine is reduced to 127 pounds.
A test in a temperature of 110 degrees showed that the inside temperature in a cloth or felt hat was two degrees cooler that the prevailing outside temperature. The same test revealed that the inside temperature in a hard hat varied from five-ten degrees cooler!
From Boulder Press date unknown.
Table of Contents.
FEDERATION NEWS.
ALAA April 2007 Report on Congressional and Government Agency Activities.
By Jon Spunaugle, CFMS Bulletin June 2007.
The U. S. Congress and the Government Land Management Agencies, US Forest Service (USFS) and Bureau of Land Management (BLM) continue to make progress on several fronts of interest to the ALAA and "rockhounds" interested in access to public lands.
The U. S Congress is moving ahead with two identical Fossil Preservation Bills (S 320 and HR 554). The Senate Bill S-320 is listed on the Senate Calendar and will be voted on in the next few weeks. Very likely shortly after the Senate resumes from the Easter Break. The House Bill HR 554 is being reviewed by two Committees; House Natural Resources Subcommittee on National Parks, Forests & Public Lands; and House Agriculture Subcommittee on Department Operations, oversight, Nutrition, and Forestry.
These committees may review the Bill and report on it. However the Speaker of the House of Representatives has the authority to place the Bill as introduced on the House calendar without comment or consultation with the committees. Comments by rockhounds on these Bills should go to your Congressional Representative immediately if they are to have any effect on the Bill's passage which seems likely. Congress is also considering 14 new Wilderness designations which will be reviewed in the next report.
The US Forest Service is continuing to push forward with land sales under the 2008 Federal Budget and the National Forest Land Adjustment for Rural Communities Act. Their recent actions have been to add additional land parcels for sale. The purpose is to raise funds for use by local communities affected by Forest Service curtailed logging activities.
Information on the parcels of land being offered for sale can be found on the Internet at http://www.fs.fed.us/land/staff/spd.html. Though most of the parcels are small isolated lands, several are not and could affect rock collecting. The ALAA urges interested rockhounds to review these parcels and report back to the ALAA on any that contain known collecting locations.
The Bureau of Land Management and the US Forest Service continue to review roads open for use by ATV's and have been holding meetings open to the public for public input. These are great opportunities for interested rockhounds to let the public land managers know their feelings on road closures. As Congress continues to reduce the funding for roads and road maintenance by the public land managers the more roads will be closed. To have an input into which roads will stay open and which will be open to ATV access you need to attend these meetings. One of our best sources of information on these input opportunities has been our association with the Blue Ribbon Coalition. They publish a wealth of information on their web site at http://www.sharetrails.org/. The information can also be obtained by researching the information on the Federal Register.
If you don't speak up and take advantage of these meetings and public input opportunities, someone else will be speaking instead of you and they may be saying something entirely different from your views.
Table of Contents.
Alert for OHV Users Participating in the Route Designation Process.
Dear BRC Action Alert Subscribers in California,
Anti-recreation activists in California have long pushed State and Federal agencies to manage Inventoried Roadless Areas as "non-motorized". At recent meetings where BRC members and staff were in attendance, several of these activists have suggested that the 2001 Clinton Roadless Rule actually precludes all active management, such as trail maintenance, of OHV use in Roadless Areas.
We have come to expect this sort of thing from California's brand of anti-recreation extremist groups. However, BRC is much more concerned about reports of U.S. Forest Service personnel in opposition to proposed route maintenance in certain Roadless Areas. While we have not been able to verify or confirm the accuracy of these reports, we thought it important to issue a Land Use Advisory to all of our members in California and other states.
The 2001 Roadless Rule (a.k.a. Clinton Roadless Rule) DOES NOT prohibit or even discourage Off Highway Vehicle use, or prohibit the management, maintenance, mapping or marking of OHV systems in Inventoried Roadless Areas in any way whatsoever. The text of the "Clinton Roadless Rule" clearly allows for vehicle travel along classified roads and trails designated for vehicle use. 36 C.F.R. 294.11 & 12 (2001) (repealed).
Indeed, some of the very same anti-recreation groups who are pushing to close Roadless Areas to motors have actually made the correct interpretation of the Clinton Rule in legal papers they have filed, stating:
"the [2001 or Clinton] Roadless Rule, even if reinstated, would pose no threat to these groups' [specifically, Cal4WD, UFWDA, ACSA and BlueRibbon] interests in off-road vehicle recreation. The rule does not prohibit off-road motorized travel in inventoried roadless areas of the National Forest System, nor does it close a single trail used by off-road vehicle enthusiasts."
This reference was made in a brief opposing OHV groups' intervention into one of the many ongoing roadless cases. These same papers further clarify that:
"even if the [2001 or Clinton] Roadless Rule is reinstated by this [ND Cal] Court as plaintiffs request, it will not prohibit a single person's off-road vehicle use or close a single off-road vehicle trail as alleged by the Off-Road Vehicle Groups' declarants." Id. at 5 (emphasis added).
BRC has made this document (Brief in Opposition to Intervention by The Wilderness Society et al (Doc. No. 79, filed March 7, 2006) in Case No CV-05-3508 (ND Cal)) available for your use and reference:
http://www.sharetrails.org/uploads/PL/IV_response_in_op_%203-7-06.pdf.
If you are participating in Travel Management planning and any Forest Service staff, contractor, employee or representative of any State agency suggests that the Clinton Roadless rule would preclude management or designation of OHV use in Roadless Areas, please immediately contact BRC at the number below.
If you are attending any of the public meetings scheduled in the next few months, and any staff or volunteer of any anti-recreation group suggests the Clinton Roadless Rule prohibits managing OHV use in Roadless Areas, please feel free to refer them to the above-cited papers filed by the Wilderness Society and dozens of other groups in the Roadless litigation.
To learn more about the ongoing Travel Management process in California or other states, visit BRC's public lands web page at: http://www.sharetrails.org/public_lands/. To receive updates and notices of public meetings, subscribe to BRC's Action Alert list:
http://www.sharetrails.org/alerts/.
Ric Foster, Public Lands Dept. Manager; 208-237-1008 ext 102.
PS: Please contact the BlueRibbon Office if you would like to receive a PDF file containing the entire copy of these papers, which include further amplification and additional citations to authority on these points and correct interpretation of the 2001 Roadless Rule.
BRC CALIFORNIA LAND USE ADVISORY From John Martin PLAC South.
Table of Contents.
LET'S GO TO A SHOW 2007.
CFMS SHOWS 2007.
AUGUST 3-5; NIPOMO, CA - Orcutt Mineral Society, St. Joseph Church, 298 S. Thompson Ave. Wes Lingerfelt, (805) 929-3788.
AUGUST 4-5; SAN FRANCISCO, CA - San Francisco Gem & Mineral Society, San Francisco County Fair Building, Ninth Avenue & Lincoln Way. Hours: Sat 10-5; Sun 10-5. Ellen Nott (415) 564-4230.
AUGUST 31-SEPT. 3; FORT BRAGG, CA - Mendocino Coast Gem & Mineral Society, Town Hall, Main & Laural. Hours: Fri.-Sat.-Sun. 10-6; Mon. 10-4. Don McDonell (707) 964-3116, 643 N McPherson, Fort Bragg, 95437.
SEPTEMBER 15-16; REDWOOD CITY, CA - Sequoia Gem & Mineral Society, Community Activities Building, 1400 Rosewood Avenue. Hours: 10-5 daily. Carol Corden (650) 248-7155, ccorden@earthlink.net.
SEPTEMBER 22; LOS ALTOS, CA - Peninsula Gem & Mineral Society, Rancho Shopping Center, Springer & Magdalena Roads. Hours: Sat 9-4:30. David Muster (408) 245-2180, colleen.mcgann@hds.com.
OCTOBER 7; FALLBROOK, CA - Fallbrook Gem & Mineral Society, Fall Festival of Gems, FGMS Museum, 123 W. Alvarado. Hours: 10-4. Mary Fong-Walker (760) 723-3484, Email: mrwizard@tfb.com, FGMS.ORG/.
OCTOBER 13-14; GRASS VALLEY, CA - Nevada County Gem & Mineral Society, Nevada County Fairgrounds, 11228 McCourtney Road. Hours: 10-5 both days. Cliff Swenson (530) 272-3752.
OCTOBER 13-14; LAKESIDE, CA - Cajon Valley Gem & Mineral Society, Lakeside Rodeo Grounds, 12584 Mapleview. Hours: 10-5 daily. David Newton (619) 390-5054, jontom@nethere.com.
OCTOBER 13-14; TRONA, CA - Searles Lake Gem & Mineral Society, 13337 Main Street. Hours: Sat 7:30-5; Sun 7:30-4. Jim & Bonnie Fairchild (760)372-5356, Sigms@iwvisp.com, www1.iwvisp.com/tronagemclub/FLYER.htm.
OCTOBER 20-21; ANDERSON, CA - Shasta Gem & Mineral Society, Shasta District Fairgrounds. Hours: Sat . 9-5; Sun. 10-4. Bill Seward (530) 365-8641.
OCTOBER 20-21; PLACERVILLE, CA - El Dorado County Mineral & Gem Society, El Dorado County Fairgrounds, 100 Placerville Drive. Hours: 10-5 both days. Jackie Cerrato (530) 677-2975, Email: jacbobcer@directcon.net, eldoradomineralandgem.org.
NOVEMBER 3-4; CONCORD, CA - Contra Costa Mineral & Gem Society, Centre Concord, 5298 Clayton Rd. Hours: 10-5 both days. Sam Woolsey (925) 837-3287.
NOVEMBER 3-4; LANCASTER, CA - Palmdale Gem & Mineral Society, 2551 W. Ave H & Hwy 14. Hours: 9-5 daily. Susan Chaisson-Walblom (661) 943-1861, SLChaissonA@yahoo.com, pgmc@anteleom.net, www.palmdalegems.org.
NOVEMBER 10-11; YUBA CITY, CA - Sutter Buttes Gem & Mineral Society, Festival of Gems, Grace Franklin Hall, 442 Franklin Avenue. Hours: Sat. 9-5; Sun. 9-4. Cliff Swenson (530) 272-3752.
NOVEMBER 17-18; OXNARD, CA - Oxnard Gem & Mineral Society, Oxnard Performing Arts Center, 800 Hobson Way. Hours: Sat 9-6; Sun 10-4. Miriam Tetrault (805) 642-5779, www.OGMS.net.
AMERICAN FEDERATION / REGIONAL
SHOW SCHEDULE - 2007.
Northwest Federation (NFMS);
August 3-5;
Butte, MT.
www.amfed.org/nfms/nfmsshow.htm.
Midwest Federation (MWF);
August 11-12;
Houghton, MI.
South Central Federation (SCMS);
September 1-2;
Arlington, TX.
Eastern Federation (EFMS);
October 6-7;
Newark, NY.
Southeast Federation (SFMS);
November 9-11;
Gulf Coast of MS.
Table of Contents.
SUPPORT AND PRACTICE
THE AFMS CODE OF ETHICS.
Dulcet Dunes.
Self-synchronized avalanches turn piles of sand into musical instruments.
By Fenella Saunders from American Scientist November/December 2006,
http://www.americanscientist.org/template/AssetDetail/assetid/54096.
The sound is unearthly, a deep drone that is a cross between a hum and a buzz. The volume is also unnerving. "It's about 110 decibels, as loud as the engines of a plane that is going by just above you," says Stephane Douady. "The human threshold of pain is 120 decibels, so this is really powerful."
Adding to the tone's otherworldliness is the inability of the human ear to localize the source of the noise. "You can find the direction if the sound's wavelength is shorter than the distance between your two ears," Douady explains. "But here, it's low-frequency sound, more than 3 meters long, so you cannot really find where it is coming from."
What are these strange emanations? They are the songs of sand dunes. Marco Polo observed "singing sands" during his travels in China in the 1200s, as did Charles Darwin in Chile. There are perhaps 100 or so places worldwide where melodious dunes exist.
Investigators have long theorized that the sounds come from grains cascading down the faces of the mounds. Douady, a physicist at the Centre national de la recherche scientifique in Paris, and his colleagues have been delving deeper into dunes in Morocco, Chile, China and Oman, and believe they can now explain the exact mechanism behind this acoustic phenomenon.
Sand avalanches don't look like much, nothing like the snow events. But under the surface, sand slides have a lot going on. As the granules get moving, they quickly sift themselves by size: The smaller ones fall through the gaps between their bigger brethren, so larger bits end up on top. A sand avalanche will typically have 20 to 30 such self-sorted strata, says Douady.
As the landslide progresses, the layers gain energy from gravity. But they also slam into the levels below them, producing shock waves that lessen the sand's speed. Thus the tiers converge to a constant velocity. But Douady adds that the friction of the grains during impact also appears to produce a wave that travels through the entire flow, coupling all motion together. As Douady and his colleagues reported in the July 7 issue of Physical Review Letters, soon all the bands have spontaneously begun moving up and down in phase. The result is that the surface pulses like the diaphragm of a speaker, emitting the booming serenade. Without this synchronous undulation, the sand might rustle, but it wouldn't sing.
The group also hauled sand back to the laboratory and set it up in channels with automated pushing plates. The sands still sang, proving that the dune itself was not needed to act as a resonating body for the sound, as some researchers had theorized. The motion is also not really stick-slip, like a violin bow on a string, because that requires two solid surfaces, says Douady.
Dunes typically have a characteristic frequency, determined by their average sand size: The larger the grain, the lower the key. However, Douady's team found that they could get dunes in the wild to hit different notes if they shoved piles of sand faster or slower than the speed normally induced by gravity, or if they moved more material than gravity would release in a natural avalanche.
Douady also found that there is a window of grain speed, above or below which the sand won't perform in nature. Too slow and there's not enough energy to produce shock waves; too fast and the sand doesn't flow but is just flung away. Height also matters. Douady believes that the coupling wave reflects back and forth inside the flowing avalanche and is only able to synchronize the movement of the sand layers if it returns at the end of one period, so that the peaks and valleys of the waveform line up and reinforce one another. If the height of the sand flow isn't within the correct bounds for this arrangement to happen, the dune may not naturally sing.
There are further complications. The grains have to be well rounded and of a small range of sizes. To make matters worse, Douady found that the sand he had brought back to his lab stopped singing after a month of experiments. After some brainstorming, he realized that all the tuneful dunes are near salt sources. "The best dunes I ever found were in deserts, but close to the sea," he says.
Sure enough, after a saltwater bath and drying, his lab sand was sonorous once more. Douady suspects that the salt catalyzes some kind of veneer on the grains' surface, but he's still looking into why that's necessary. The mysterious dunes, it seems, aren't quite ready yet to give up all of their secrets.
Listen to the dunes at http://www.lps.ens.fr/~douady/.
Table of Contents.
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