Welcome rock hounds!

Turritella agate is no longer placed in the Fresh Water Genus Goniobasis, but is now the fresh water species Elimia tenera (Hall, 1845) from the Family Pleurocerida. Dr. Warren Allmon, the Director of Paleontological Research Institute is a world Authority on the turritellidae and Pleuroceridae has and is doing research on these Gastropods.
Let's discuss the WYOMING lapidary material known as turritella agate. 
Old timer rock hounds called it turritella after the salt water variety snail agate they found in Texas and California. Our Wyoming species were FRESH WATER. The age is 52 million year old Fort Laclede Bed, Laney member of Green River eocene.

Above, black and blue chalcedony infilling. Most individual snails or techically gastropods have fossil ostracodes (tiny fresh water shrimp shells) preserved in them and in the "fossil soup" as this was a shoreline deposit on the windward shore of ancient Lake Gosiute (google search).
DIFFERENCE VISUALLY: the saltwater turritella gastropod is long and slender to skinny, much skinnier than our former Goniobasis which is skinny already!

Although some material is found west of Green River and other areas, the best place to collect is about 8 miles crow-flying south west of Wamsutter, Wyoming which is located on I-80 mile marker 162. The gas and oil developement in the Barrel Springs area has changed the roads so often in the past few years that directions and maps are outdated seasonally. The historic metal stock shed is still in place last visit, and may be the only recognizable feature left. 3,000 new wells in the past three years!

Wild horses guard the secret back way in.
Do not go collecting here  when it is raining as the area will rapidly become knee deep in slippery gumbo mud.  Chains mandatory when wet, getting one's self stuck in barrow ditches is optional. Don't count on your cell phone rescuing you here.
The collecting area now days can be driven right by with out even noticing due to the reduced collecting, growth of sagebrush, and high level of energy developement. Caution: big rig trucks! Good news is there is a new Subway sandwich shop at the new truck stop in Wamsutter.

When collecting, look for the better 3"- 4" thickness and the black coloration, it is the best quality. The tan tinted or gray tinted material did not get the best silification and is thus softer, especially in the center cuts. The six inch thickness is softer in the center as well. I think the better materials come from the areas with thick tan caleache present.
Cutting: This agate cuts hard and tough. Be sure to set saw feed on SLOW and use good quality oil if you value your blade.  When cutting orient the rough so a cut lengthwise with the snails is a must or you will get little circles of cross cut snails instead of the long side view.  Note these are fat.

The digging tools needed are very basic tools.  Shovel, prybar and five gallon buckets for carrying. The BLM advises the 25 pounds per day wood collecting regulations apply. Most of the area is on patented Anadarko lands or state lands though. 
The market price for purchasing this material if you are unable to collect in person has been traditionally at $2 a pound for over 30 years and that price seems to be stable today. I have heard of spot market prices going as high as $4/lb and sometimes I have seen bulk 50 pound lots at $1 a pound. The ebay market will fluctuate depending on the source and distance from SW Wyoming. Cut material goes higher but one gets a better idea of the quality that way. All material, even the "good stuff" will have some defects in the form of voids and fractures.

• Look for quality not quantity, there is plenty left.
• The tan caliache can be removed with muratic acid-safety first, wear gloves and glasses!
• Inspect for fractures in the field, don't bring home junk rock. Too much weight will affect your gas mileage at 7,000' elevation.
• A recent email asked me about "the good stuff". Even the good stuff will have minor fractures and voids and the cabber MUST selectively cut around the bad spots for the most part. There is no golden fix to "cracks and fractures" (try paleo bond thick to fill in fractures), all the "good stuff" is still NOT PERFECT. Those expecting perfection in turrietella will sadly be disappointed. 1-10 million years on Wyomings wintry and hot high desert will surely affect the specimens.
  
• Orient correctly before cutting. Don't make wasted cuts, it will wear on your saw blade.
• It will polish very well-patience is a virtue, as stated above, work your cabs out around the fractures and fill the voids with clear crack filler.

This is  great material for belt buckles, bolo ties, and bookends.
HINT:  When tumbled, it will make excellent baroque wire wrap gems.   Slice first, pre form shapes, and then tumbled correctly. Will take an excellent polish and you will have some excellent quality baroque high end pieces for wrapping. My favorites are in silver!

USE EXTREME CAUTION!

     
   Collecting at the location: don't let the killer whitetailed prarie dogs get you or your lunch! They will just stand there, waiting, in their best meercat posture.  Eerily...waiting for your next mistake!

As with all Wyoming collecting, fill in your holes and take your trash home with you.

Be sure to bring your camera as antelope, wild horses, eagles, hawks, elk, open range cattle, rare jackalope, wolves, badgers, and wild killer praire dogs abound :>) There are no snakes at this location but watch for  small scorpians and some spiders. Nearest open  vacancy motels are at Rock Springs or Rawlins. Wamsutter motels are enguaged in an energy boom. Best times to collect are June, July, August. Muddy roads in April, May, and  big game hunting is very prevelent in September, October, and November. December through March is WINTER.

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