rollingstone
starting to spend too much on rocks
Member since July 2009
Posts: 236
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Post by rollingstone on Mar 4, 2006 3:14:37 GMT -5
This is turritella agate polished in a tumbler. Soft white (non-silicified) areas can cause major pitting problems and a lack of shine -- in my case, these are the top 10% of stones I tried. The other 90% ranges from having minor blemishes to being absolute junk.
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Post by driftwood on Mar 4, 2006 3:29:28 GMT -5
Rough
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jrtrio
has rocks in the head
With10 tumblers tumbling the sound is so delicious!Send me more of those little red fellas, please?
Member since February 2006
Posts: 535
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Post by jrtrio on Apr 21, 2006 19:13:50 GMT -5
But as you can see from the finished product of the better polished stones, they are well worth the effort. I have found that when tumbling Turritella that it should be tumbled by itself. And if you are lucky enough to have a "toy" tumbler, or what is really an 8oz tumbler, gathering a load of 2/3 the barrel and the rest of plastic pellets you can really get some spectacular results with a much higher success rate. I'll post some pictures when I've done tumbling what I have.
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beechcomber
spending too much on rocks
Summertime!
Member since March 2006
Posts: 345
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Post by beechcomber on Apr 21, 2006 20:48:47 GMT -5
wowh...those are beautiful. thanks for sharing the knowledge too.
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Post by Cher on Apr 23, 2006 15:58:27 GMT -5
Considering it's a rock with fossil shells in it, anyone know how it came to be named Turritella agate?
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Rockygibraltar
fully equipped rock polisher
Member since February 2006
Posts: 1,404
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Post by Rockygibraltar on Apr 23, 2006 17:56:29 GMT -5
Glorious polish Don. If I remember right, it's named after the snails that belong to the Turritella group.
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Post by deb193 on Apr 27, 2006 13:11:27 GMT -5
Good web site: www.priweb.org/Research/Turritella%20Agate.htmDespite its name, “Turritella agate” is not made of fossil snails of the genus Turritella. This has been realized by professionals and many amateurs for a long time, but the name (and the confusion it promotes) have persisted. The snails are actually properly refereed to as Elimia tenera, in the family Pleuroceridae. The rock in which they are so abundant varies from a soft sandstone to a dense chalcedony. It is this dense silicified rock that is so popular with gem and mineral hobbyists, and also (unfortunately) with purveyors of "new age" ideas of crystal healing and the like.
Elimia agate comes from the Green River Formation in southwestern Wyoming, northeastern Utah, and northwestern Colorado, from layers deposited in an series of ancient lakes that geologists call Lake Gosiute and Lake Uinta, in the early and middle parts of the Eocene Epoch, between around 53 and 42 million years ago. These rocks, in other words, formed in fresh water. The real Turritella is a group of snails that live only in the ocean. The shells of Elimia are distinguishable from real Turritella by being generally shorter and wider, but especially in having axial as well as spiral sculpture on the shell.
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casco1
noticing nice landscape pebbles
Member since December 2005
Posts: 79
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Post by casco1 on May 11, 2006 23:44:36 GMT -5
Would love to do a batch or two of these alone. Have a few pieces in mixed batches that turned out as either crap-or really nice. But they were only small pieces.
There also seems to be quite a bit of difference in the quality of the stone. Some of it is much softer and grinds away very easily while other pieces in the same batch seem to polish well.
Was thinking of looking too some cabs as well. Would be a really nice belt buckle & bola set.
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rollingstone
starting to spend too much on rocks
Member since July 2009
Posts: 236
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Post by rollingstone on May 24, 2006 14:14:51 GMT -5
Casco, you are right about the quality, an awful lot of turritella seems to have soft, white, non-silicified areas that end up pitting, very frustrating. There is some good material that seems to be silicified throughout, but it's tough to find, at least on ebay. I would recommend never buying turritella unless you see the actual lot you are buying, either in person or from some good photos. Here is nice one-inch thick slab (about 2 pounds) that I located after about a year of sporadic searching on ebay, which seems to be good and solid throughout. It isn't polished, the photo was taken wet. Nephrite's piece above looks nice and solid too. I hope you manage to find some nice turritella!
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Post by driftwood on May 24, 2006 22:42:16 GMT -5
Don, I think that slab your holding would make a perfect CABZILLA.
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jrtrio
has rocks in the head
With10 tumblers tumbling the sound is so delicious!Send me more of those little red fellas, please?
Member since February 2006
Posts: 535
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Post by jrtrio on May 27, 2006 19:16:53 GMT -5
I really do love Nephrites sample! It's so rough and those shells just jump out at you!! If I were you Nephrite, I wouldn't polish that. I would just put it in your own collection for people to ooh and ahhh over the zillion year old animals!
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