ROCKWOOD ROCKHOUND NEWS for OCTOBER 2000

Our Special Guest

Dr. Michael Fuller head of the department of archeology from Florissant Valley Community College, will be our October speaker for the meeting of the Rockwood Gem and Mineral Society. The meeting will be held at the Daniel Boone Library, 300 Clarkson Rd. Ballwin. Mo. 63011 on Friday October 20, 2000. Time will be 7:30 PM.

Guests are welcome to all meetings. We have had Dr Fuller speak for us the past several years on his dig at Tuneinir (Syria). He and his wife Neathery have worked this dig for the past 13 years and have found some very important pieces of history both of religious and secular interest.

For more, Click here

Kudos!
Congratulations to our members who won trophies for their Competitive Exhibits at the recent MWF Show at Queeny Park:

Joan Schlichter for her Trophy #27, Educational I (Petrified Wood)

Barbara C Sky for her Trophy #32 Fossils (mollusks)

Hank Schlichter received a blue ribbon for his exhibit on Petrified Wood

Weather permitting, we will go back to the gravel bar on Saturday, October 21. The river was way down this summer. Then we had rain, it flooded and is down again so there should be some new material deposited. Last time we found a plethora of agates, jasper, fossils, and even a couple of arrowheads. Bob Morris will have more information for us at the October 20 meeting.

I was admiring a necklace made of alligator teeth when its owner declared, "It's more valuable than pearls!" 
I asked why?
She replied, "Anyone can open an oyster"

Paleobotanists  at Sul Ross State University, Alpine, Texas, recently restudied a Collection of petrified wood in a storage cabinet. They discovered a fossilized termite nest in a small limb section. The limb had been collected from the Big Bend National Park area during the l960's,
They dated evidence of termites actually chewing wood. A limb had been bored out and partially filled with fecal pellets. Since the pellets were mostly cellulose, they were preserved the same as the wood. rivers and forests.

To clean and shine most druzsy specimens, use "Easy Off" oven cleaner ("fume free" is OK). Spray
the specimen and then leave it overnight in a closed container or bag before rinsing. This even works on iron stained quartz crystals. 

Clarkson Jewelers
Sapphires, Opals, Topaz: Beautiful Harbingers of Fall

September - Sapphire
Whenever we think of sapphire, we think blue. And in fact, this gem, of the corundum group, is called "sapphire" when it is a deep blue. Red corundum is ruby. All other colors are called "fancy" sapphire and each is defined by color, such as green sapphire, pink sapphire, and so on. Sapphire from Burma and Kashmir are often the closest to the highly prized, pure spectral blue. Valued for its hardness and brilliance, sapphire is also found in a translucent variety that shows a six-rayed "star" effect when cut into a cabochon (rounded stone with no facets).

October - Opal
Opal, at its finest, brings to mind the colorful beauty of autumn, making it t perfect birthgem for October. Unlike any other gem, opal has a unique rainbow-like display of color. Opal is made of a series of hydrated silica spheres. The arrangement of these spheres --their variation in size and pattern -- is the physical cause of each opal's unique multi-color look.

November - Topaz
Topaz, the accepted symbol of love and affection, is also the birthgem of November- and the anniversary gemstone for the 23rd year of marriage.  While topaz is generally thought of as a transparent yellow, it is also found in orange-yellow, yellow-brown, orange-brown, light to medium red, and light to medium deep blue. Ma topaz are heat treated to permanently improve their color. The name "topaz" was derived from the Greek word for" shine," which also implies "fire."

This month I thought we would try to decipher a group of minerals that is very diverse and can also be very complex. You see them everywhere when at shows. They are in almost everyone’s mineral collection. They are found throughout the world, and they are naturally occurring and man-made. And so here are:

An 18^th century Swedish mineralogist and chemist by the name of Alex Fredrik Cronstedt (Dec. 23, 1722 - Aug. 19, 1765) originally coined the current term "Zeolite" that we use today. Zeolite is a synthetic Greek word formed from "Zein" and "lithos" meaning a "stone that boils." A. F. Cronstedt observed that by the rapid heating of a natural zeolite, it would begin to dance around as the water evaporated.

Zeolites, in the class of Tectosilicates, are a framework of silicates consisting of interlocking tetrahedrons of SiO4 and AlO4. And in order to be classified as a zeolite, their ratio of (Si + Al) /O must equal ½. They are characterized by their large vacant structural spaces, which allow for cations such as sodium, potassium, barium, and calcium to enter their framework. Their ability to lose and absorb water without damage to their crystalline structures makes them very valuable. They naturally form in nature by a chemical reaction between volcanic glass and saline water. Temperatures favoring the natural growth of Zeolites range from 27 – 55 degrees centigrade. Their pH typically runs between 9 -10. Naturally forming Zeolites require approximately 50 – 50,000 years to complete.

Zeolites typically associate in vugs, amygdales, and veins of alteration volcanic rock, alkaline lake deposits, or open hydrologic systems. In the United States commercial deposits of Zeolites are found in Arizona, California, Idaho, Nevada, New Mexico, Oregon, Texas, Utah, and Wyoming. Some of the finest specimens to grace many mineral collections come from the flood Basalt’s of India, commonly referred to as the "Deccan Trap." The most extensive mining site for this material has been in Maharashtra State near the town of Bombay, where peacock blue cavansite and apple green apophyllite hails.

Zeolites have been placed into three different structural variations:

• Acicular or needle-like prismatic crystals (i.e.: natrolite)
• Flattened or tabular crystals usually with good basal cleavage (i.e.: heulandite)
• Framework structure crystals which are more of less equant in dimension (i.e.: chabazite)

Because of the nature of the name "Zeolite," it often becomes confusing as to which minerals are really Zeolites. We have the tendency to class many minerals as Zeolites when in fact many are really associated or secondary minerals.

• The most common Zeolites are: analcime, chabazite, clinoptilolite, epistilbite, erionite, ferrierite, heulandite, laumontite, mesolite, mordenite, natrolite, phillipsite, scolecite, stellerite, and stilbite.

• The most commonly associated or secondary minerals with Zeolites are: apophyllite, calcite, prehnite, gyrolite, and okenite.

A complete list of species and series members currently recognized in "The Zeolite Group" by the International Mineralogical Association (IMA) was reviewed in Mineralogical Record v. 30 #1. Here in it lists 13 series minerals and 52 single minerals totaling 87 different minerals that belong to the group.

Zeolites over the years have been used commercially for many uses. It is interesting to note that in 1998 a study by Addwest Minerals International Ltd. revealed that the U.S. alone utilized 38,500 tons of natural Zeolites for it’s own use. Some of the more common uses of Zeolites in this country are:

Pet litter, Animal feed, Soil conditioners and growth media, Wastewater cleanup, Odor controls,

Desiccants, Gas absorption, Catalysts, Oil absorbents, Aquaculture, and Water purification.

Here are some links for further information on Zeolites:

The Zeolite Group of Minerals – http://mineral.galleries.com/minerals/Silicate/ZEOLITES.htm

Indian Minerals – http://www.nvo.com/indianminerals/door/  

The Zeolite Group by the IMA – http://www.nvo.com/indianminerals/htmlpage24

Zeolites & Assoc. Minerals from Maharashtra State – http://www.nvo.com/indianminerals/articlesandinformation 

International Committee on Natural Zeolites – http://icnz.lanl.gov/site_list.html

Minutes of the Rockwood Rock Hounds Meeting of September 15, 2000

The meeting was called to order by Pres. Bob Morse at 7:25 p.m.
There were eight members and two guests present.
SECRETARY'S REPORT-none
TREASURER'S REPORT-none
FIELD TRIPS: The river is down so we plan a field trip on Saturday, Oct. 21. Bob is also checking into a creek at Troy, Mo for geodes.

Bob said we had a successful show at Queeny Park. He did not know how much money was taken in yet, but everyone seemed happy.

Dr. Fuller will be our speaker at our next meeting. Bob hopes to send out cards inviting people to come.

Dr. Bob Osbourne gave a very interesting program on field geology and slides of Mammoth Cave in Kentucky.

Remember the meetings are at 7:00 pm on the third Friday of each month at the Daniel Boone Library on Clarkson Rd.

RESPECTFULLY SUBMITTED, Helen Heitland, Sec.