December 2013 Vol. 52.12 Austin Gem & Mineral Society Each one teach one THE AUSTIN GEM AND MINERAL SOCIETY, INC. (AGMS) is a member in good standing of the South Central Federation of Mineral Societies and the American Federation of Mineral Societies. Its editors are also members of SCRIBE. The club address is 6719 Burnet Lane, Austin, Texas 78757, and phone (512) 458-9546. The AGMS is a 501(c)(3) nonprofit organization. Visit our website at www.austingemandmineral. org Contact our webmaster for website updates at DiannH@ austingemandmineral.org. PURPOSE The purpose of the AGMS is to promote interest and education in the various Earth Sciences and other related subjects. MEETINGS The society meets at 7:00 p.m. the fourth Thursday of every month except October, which is show set up day. The November meeting will be held on the THIRD Thursday. December is the Officers’ Induction Banquet held on a date to be determined. Board meetings are held the first Tuesday of every month. Show committee meetings are held on the third Thursday of each month. All meetings are open to anyone. Society officers are listed on the second page of this publication. Please feel free to contact any of them for information Dues for 2013 Annual membership dues are: Adult-$30.00 Couple-$40.00 Junior--$4.00 Table of Contents General Meeting Minutes............................Page 2 Board Meeting Minutes...............................Page 4 Harriet Strieber ............................................Page 4 What’s Under the Earth’s Surface...............Page 4 Dioptase......................................................Page 5 Christmas Banquet .....................................Page 6 Regular Features.........................................Page 6 AFMS Field Trip in Montana........................Page 6 Merry Christmas all you rockhounds, lapidary artists, gemologists, etc. This has been a fruitful and interesting year. I have enjoyed being your president for the last two years and I appreciate all the help I had from the Board and the membership. I know your new officers and board will do a good job for you next year. My wish list for 2014 includes more field trips, especially nearby, more classes, and more participation in the Show Committee. The Show Committee will not only be planning for the 2014 show, but also for the national show here in 2015. I will help where I can and encourage all of you to get involved as much as you are able. Pauline The Stone Chipper Presidential Message Happy Holidays!
Transcript
December 2013 Vol. 52.12Austin Gem & Mineral Society
Each one teach one
THE AUSTIN GEM AND MINERAL SOCIETY, INC. (AGMS) is a member in good standing of the South Central Federation of Mineral Societies and the American Federation of Mineral Societies. Its editors are also members of SCRIBE. The club address is 6719 Burnet Lane, Austin, Texas 78757, and phone (512) 458-9546. The AGMS is a 501(c)(3) nonprofit organization. Visit our website at www.austingemandmineral.org Contact our webmaster for website updates at [email protected].
PURPOSEThe purpose of the AGMS is to promote interest and education in the various Earth Sciences and other related subjects.
MEETINGSThe society meets at 7:00 p.m. the fourth Thursday of every month except October, which is show set up day. The November meeting will be held on the THIRD Thursday. December is the Officers’ Induction Banquet held on a date to be determined. Board meetings are held the first Tuesday of every month. Show committee meetings are held on the third Thursday of each month. All meetings are open to anyone. Society officers are listed on the second page of this publication. Please feel free to contact any of them for information
Dues for 2013Annual membership dues are:
Adult-$30.00 Couple-$40.00 Junior--$4.00
Table of Contents
General Meeting Minutes............................Page 2Board Meeting Minutes...............................Page 4 Harriet Strieber............................................Page 4What’s Under the Earth’s Surface...............Page 4Dioptase......................................................Page 5Christmas Banquet .....................................Page 6Regular Features.........................................Page 6AFMS Field Trip in Montana........................Page 6
Merry Christmas all you rockhounds, lapidary artists, gemologists, etc.
This has been a fruitful and interesting year. I have enjoyed being your president for the last two years and I appreciate all the help I had from the Board and the membership. I know your new officers and board will do a good job for you next year.
My wish list for 2014 includes more field trips, especially nearby, more classes, and more participation in the Show Committee. The Show Committee will not only be planning for the 2014 show, but also for the national show here in 2015.
I will help where I can and encourage all of you to get involved as much as you are able.
Alan Cherepon opened the meeting at 7:05 p.m. and announced Robert Morriss’ program topic, Opal Mining in Australia. Robert explained that after World War II opal mining started on Lightning Ridge in New South Wales. He and Charlotte visited and photographed that location and several other mining operations during their three-month trip.
Laird Fowler, coordinating offerings from the library with Robert’s topic, brought two books to the members’ attention: A Field Guide to Australian Opals and Opal Adventures.
President Pauline Denson acknowledged visitors Roy Steadman and Rose Farmer.
The October minutes were approved as printed in The Stone Chipper.
Charlotte Morriss reported that membership now stands at 196 adults and 13 juniors, and that 10 applications came in from the show.
Dues and Banquet: Pauline reminded that dues can be paid now and that Charlotte Morriss is taking reservations for the Installation Banquet on
3 Stone Chipper December 2013
December 12th ($10 per person). For the banquet, members are urged to bring a dessert to share and, if you wish to participate, a rock-related gift to exchange ($10-$15 value) marked for male or female. Cabbing Contest: Laird Fowler announced the winners: Chip Burnette for his Traditional cab of Montana Agate, Brian Wetzig for his Free-Form cab of copper, and Terry Barry for his quartz cab.Laird said that next year’s material would be dinosaur bone.
Field Trips: Chip Burnette invited any interested members to join him in Hot Springs, AR, next week. He also said that the American Federation is sponsoring a trip to the Terry, Montana area to search for Montana agate and fossils the last week in July.
Elections: Marilyn Gilbreath thanked the other committee members, Carolyn Perkins, Richard Dorsey and James Mercier, then introduced the slate of officer and director nominees:President Josie Middleton, 1st VP Les Postlethwait, 2nd VP Kathleen Howard, Treasurer Charlotte Morriss, Secretary Shawn McMahon and Directors Cindy Murphy, Dee Fly and Sian Schilhab. Pauline called for nominations from the floor, and with no further nominees, the vote was unanimous to elect the slate. The incumbent directors are Lou Pulliam, Laird Fowler and Craig Brandt.
Announcements:Fossil Fest - December 7 & 8 at Old Settlers Park, Round Rock: Sue Postlethwait asked for volunteers to cab fossil horn and coral and work the Dino Rub table. She’ll send a signup email with a list of shifts and times. Admission is free for volunteers, otherwise, $3 for adults. Food items are for sale at the event.
Attendance: 56 members and 2 visitors.
Door Prize Winners: Diann Hill, Brian Beard, Paul Bordovsky, Grace Folsom, Cindy Murphy, Susan Post, Joan Corte, Shawn McMahon, Dee Fly and Joe Perkins.
Robert Morriss, November General Meeting speaker, points out Lightning Ridge area of New South Wales where he and Charlotte visited opal mines.
Photo by Joe Perkins
Show and Tell: Ron Carman brought green fluorite, strawberry quartz and strontianite.Alan Cherepon had material from Sterling Hill, NJ.Jackie Fisher showed her two new books on fluorite.
The meeting adjourned at 8:05 p.m. and refreshments were served.
Marilyn Gilbreath, for Secretary Joyce Hrapsky
Photo by Joe Perkins
Marilyn Gilbreath introduced 2014 slate of officer and director nominees. Pictured from left, Sian Schilhab, Director; Charlotte Morriss, Treasurer; Les Postlethwait, 1st VP; Josie Middleton, President; Marilyn Gilbreath (Nominating Committee Head); Pauline Denson (President 2012 & 2013); Kathleen Howard, 2nd VP; Shawn McMahon, Secretary; Cindy Murphy, Director; Dee Fly, Director.
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the AGMS Board of Directors held a regular meeting on December 3, 2013. Ten board members and four club members were present. A complete set of minutes is available upon request.
Old Business:
Treasurer’s Report: - Checking, savings and investment account balances were given.
Door replacement - A sheet of wood will be bolted over the existing glass.
Audit Committee - Will meet in the next couple of weeks.
New Business:
Discussion of parking - the neighboring tenants will be advised of the club’s regular meeting times. Adding hash marks on the club’s parking areas was discussed
Librarian required at general meetings - the Library Committee will coordinate attendance.
Joyce Hrapsky, 2013 Secretary
Wishing You a Speedy Recovery, Harriet!
How Do We Know What’s Under the Earth’s Surface?
AGMS Board Meeting SynopsisDecember 3, 2013
Laura Dow posted a message on the AGMS list concerning Harriet Strieber’s recent abdominal surgery.
Harriet is currently recovering at the Summit at Lakeway, a rehab center, following her recent surgery. For those wishing to express their concern, please send cards and e-mails rather than calling. Harriet’s address is: Summit at Lakeway, 1915 Lohmans Crossing Rd., Room 5, Lakeway, TX 78734. Hope you’re up and feeling better soon, Harriet.
We can’t drill down to the center of Earth, or even beyond the thin crust to investigate the mantle below. So, we must use indirect methods to figure out the structure, composition, and variations in the crust and upper mantle. These five investigative tools help scientists figure out what lies beneath the surface of Earth.
Seismic Reflection and Seismic Refraction are two seismic techniques that measure the travel time of waves of seismic energy generated from shots (such as explosions, vibrations, or weight drop) on Earth’s surface. The waves travel through the subsurface, and then back to arrays of highly sensitive ground motion detectors (geophones) on the surface. In the subsurface, the seismic waves encounter interfaces between materials with different seismic velocities, often created by geologic materials or rock layers of different densities. A portion of each seismic ray that strikes a density interface is refracted (bent) into the underlying layer or along the interface, and the remainder is reflected (bounces) directly back to the surface. The geophones measure differences in the travel times of the seismic rays caused by the interfaces, which are then developed into two-dimensional or three-dimensional images showing underground structures and layers. Seismic refraction surveys are much less costly, but reflection surveys generally have better resolution and are more effective for deeper targets. Both are limited to the upper crust of Earth.
Seismic Tomography is an imaging technique that uses seismic waves generated by earthquakes to create computer generated, three-dimensional images of Earth’s interior, including deep into the mantle. Man-made explosions in boreholes can be used for more localized investigations. Scientists compile digital earthquake records from hundreds of seismometers all over the world to calculate the average speed of different types of seismic waves. Then, they map out regions where the waves traveled slower or faster than average. Waves travel faster through cold, stiff materials, like a tectonic plate subducting into the mantle, and slower through warmer materials, like hot
Article by Douglas Bland, New Mexico Bureau of Geology & Mineral Resources
Stone Chipper December 20135
molten rock rising toward the surface.
Gravity Surveys use instruments that contain a tiny mass attached to a sensitive spring to measure slight differences in the strength of Earth’s gravitational field. This field is affected by the density of subsurface rocks, among other factors. Different rock types have differentdensities. For example, igneous rocks in general are more dense than sedimentary rocks, so the tiny mass in the instrument will be pulled downward more strongly above a buried igneous rock compared to a buried sedimentary rock. Measurements are taken in grid patterns, which are transformed into maps showing density variations. These are used to model images of the subsurface geometry of different rock bodies, including location, size, and rock type.
Aeromagnetic Surveys use a magnetometer aboard or towed behind an aircraft to measure minute differences of Earth’s magnetic field. These differences are caused in part by differing concentrations of magnetic minerals in Earth’s crust, most commonly the iron mineral magnetite. Because rock types differ in their content of magnetic minerals, magnetic maps can be created that allow visualization of the geologic structure of the upper crust in the subsurface, particularly the geometry of igneous intrusions or ore bodies, and the presence of faults and folds.
From The Trilobite Sept. 2012 via The Quarry Dec. 2012
This month we are featuring the mineral dioptase, hydrated copper silicate, CuSiO3 -H2O. It is a sili-cate mineral, subclass cyclosilicates. Dioptase is one of my favorite copper minerals due to the beautiful green color of the crystals. Dioptase is found in the oxidation zone of copper deposits and in cavities in the rock associated with those deposits. It is a minor ore of copper. But it is primarily used as a mineral specimen. Some associated minerals are dolomite, calcite, cerussite, limonite, chrysocolla and other copper minerals. Noted specimens have been found in Tsumeb, Nambia and Zaire in Africa. In the USA it is
found in California and Arizona. Other noted locations in the world are in Chile and Russia.
Dioptase is in the hexagonal crystal system. Typically it is found in stubby, prismatic, bright emerald green crystals with rhombohedral terminations. It also is found as a crust and in massive forms. Crystals are transparent to translucent with a vitreous luster. Color is dark green. Streak is a pale greenish blue. It is brittle with a conchoidal fracture. Specific Gravity is 3.3 to 3.4. Hardness is 5 which is harder than most copper minerals. It is soluble in hydrochloric acid, staining the solution blue.
Dioptase takes its name from the Greek dia and optazein meaning “to see through”.
I used the following reference materials in preparing this article. Field Guide To Rocks And Minerals by Frederick H. Pough. Mineralogy For Amateurs by John Sinkankus. Simon & Schusters Guide to Rocks And Minerals. The Audubon Society Field Guide To North American Rocks and Minerals. Amethyst Galleries Mineral Gallery on the internet (address http://mineral.galleries.com).
From Canaveral Moonstone October 2012 Via The Quarry, December 2012
Dioptase - Mineral of the MonthBy Dave Jackson
photo of Dioptase from Tsumeb Mine, Namibia by Didier Descouens, from Wikipedia
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AGMS List Serve
If you are currently not a member of the AGMSList and would like to be, please email Diann Hill at [email protected]. It’s the best way to keep up with the latest AGMS happenings.
Refreshments!
Please contact Katheen Howard ([email protected]) if you have refreshment questions or have signed up and find you will not be able to attend that meeting.
If you have trouble remembering when it is your time to bring something and would prefer not to bother, Kathleen is happy to accept cash donations as well.
Stone Chipper Ads
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There is no extra charge for full color, but mail out copies will be black and white only.
The Stone Chipper can now accept non-political AGMS Board-approved paid advertising. If you are interested in placing an ad or have questions about the process, please contact Stone Chipper editor Carolyn Perkins at [email protected].
You can choose from a variety of sizes for your print-ready ad:
THANK YOU!
Each month Jim and JoAnn Wiersema & Cora Caffey of Horizon Environmental Services print, fold and seal the Stone Chipper for mailing to those club members who do not have computer access and for non-members interested in finding out more about the club. This is a real cost savings for AGMS and we appreciate their generosity.
Multi-Federation Field Trip -- Make Plans to Attend NOW!By Doug True, Field Trip Chair, AFMS
Mark Your Summer Calendar!July 31-August 4, 2014
DecemberChristmas BanquetThursday, Dec. 12
Club members who have bought their tickets, don’t forget the Christmas banquet gathering will begin at 7:00 p.m. Dinner will be smoked turkey & trimmings. Bring a dessert and a wrapped gift marked for male or female if appropriate. Gef Fisher will be there at 4:00 and will welcome help setting up & cleaning up afterward.
The town of Terry, Montana may be small, but they are planniung on rolling out the red carpet for us as they host the AFMS 2014 Multi-Federation field trip gathering. The dates are July 31-August 4, 2014, so mark your calendars and get ready to register!
Terry is right in the middle of some of the best Montana rock hounding areas. We’ll have numberous trips to the Gravel Bars on the Yellowstone River; productive areas that I’ve been hunting on annually for 40+ years. Many are accessed only through private property, but
Stone Chipper December 20137
Have a Safe, Happy Holiday Season & a very MERRY CHRISTMAS!!
permissions have been granted. We’ll be hunting for Montana agates, jasper, pertified wood, fossil coral, stomatolites, and numerous other “oddities.”
We’ll have numerous trips into Montana fossil country to the Pierre and Bear Paw formation areas, and we’ll collect ammonites, baculites, scaphites, natiloids and many other shells (70-95 million years old) in the ancient sea bed areas. We are also working on trips to serveral areas where we can collect dinosaur fossils from the Hell Creek Formation. More information will be forthcoming as plans are solidified
In addition, we’ll have an opportunity to take a guided tour through the Eastern Montana Badlands - a once in a lifetime opportunity.
Start planning your collecting vacation now. Kids are welcome!!!! What could be better than four days in Eastern Montana with a chance of collecting wonderful material.
But wait, there’s more....The town of Terry is allowing us to use their 2 block city park for dry camping and other activities. We’ll have pot luck dinners, a barbecue and much, much more.
For more informaiton contact Doug True, Field Trip Chair, (406) 670-0506, or email <[email protected]>.
Chip Burnette contacted Doug and learned that Terry has a hotel and a motel (600 pop.), with a total of about 45 rooms, and 3 small RV parks with hookups (@ 35 spaces). There is also another town with more services 38 miles away. Doug can provide lodging phone numbers. Sounds as though, if we are interested in going, we had better get a move on.
“Happy Christmas,” 1891, by Johansen Viggo (1851-1935)Wikipedia
The Stone Chipper is the official publication of the Austin Gem and Mineral Society. It is published monthly in Austin, Texas. Expanded minutes of Board Meetings are available upon request. Note: Clip art images are under Copyright 2013 by the AGMS and its licensors. All rights reserved. Unless otherwise noted, text items in The Stone Chipper may be reproduced in other nonprofit publications as long as proper credit is given to the author and The StoneChipper. All authors who make submissions to this newsletter are presumed to agree with this policy.
The Stone ChipperCarolyn Perkins, Editor6719 Burnet LaneAustin, Texas [email protected]
