herchenx
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Post by herchenx on Mar 26, 2014 18:45:48 GMT -5
Slabbed a bit of Turritella Agate (which is misnamed - the snails are not Turitella, they are Goniobasis: www.google.com/search?q=Goniobasis&espv=210&es_sm=93&tbm=isch&tbo=u&source=univ&sa=X&ei=MmUzU5ezAcbuqwH2g4GIBQ&ved=0CCcQsAQ&biw=1366&bih=643)ANYHOO Because you want to cut across the long side of the snails (not across the "circle") I usually only get a couple slabs out of a chunk. I have a good amount though so in the end I can get a lot of slabs. I had to lop off one end because it was too long for the saw, but when I oriented it into the saw blade it was about 1/4" too tall. I figured I'd take my chances, what with a brand new blade and all, and let it run anyway. Fortunately it did fine but these were as large as I would ever slab on this 12 incher. Here are the slabs: I was pretty happy with the result, sometimes you don't get as many lined up as this, and these slabs are nice and solid and pretty dark agate.
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Post by Jugglerguy on Mar 26, 2014 18:57:05 GMT -5
Those are cool, John. I'm not sure I understand how the snails are oriented, though. Are they randomly oriented, so that getting a good slab is all luck? Or did the snails tend to land horizontally as they settled to the bottom of the ocean millions of years ago, making it important to choose the correct way to saw?
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grayfingers
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Post by grayfingers on Mar 26, 2014 18:58:51 GMT -5
That is some nice solid looking Turritella! Big slabs!
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herchenx
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Post by herchenx on Mar 26, 2014 19:15:30 GMT -5
Those are cool, John. I'm not sure I understand how the snails are oriented, though. Are they randomly oriented, so that getting a good slab is all luck? Or did the snails tend to land horizontally as they settled to the bottom of the ocean millions of years ago, making it important to choose the correct way to saw? They (I believe) were freshwater snails from some mega lakes that were here a bajillion years ago. They tend to lie on the x, y axis versus being vertically oriented on the z axis. This agate is in plates 3-6" thick where I've found it, and if you make vertical cuts you end up with mostly circles. If you make cuts along the horizontal you get more of the pretty half-snail patterns.
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Post by Jugglerguy on Mar 26, 2014 19:24:54 GMT -5
That's what I figured, but thanks for clarifying.
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rykk
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Post by rykk on Mar 27, 2014 3:17:52 GMT -5
Nice stuff! And it takes a glass shine, too. BTW - I'm just guessing, but I think the reason they called it, "Turretella" is because those types of shells are, typically, called "turret shells" by folks who are into seashells. That was my previous obsession before my rockhounding phase and I was always hoping to find a few whenever I went shell hunting here in Florida. Personally, though they are bulbous like some turret shells, they're not a squat shape and their length makes me think of them as auger shells. Who know, maybe the modern turrets and augers evolved from these? C-ya, Rick
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herchenx
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Post by herchenx on Mar 27, 2014 9:40:30 GMT -5
Hi Rick, I bet you're right about the origin of the name "turritella" but that is a different type of snail: en.m.wikipedia.org/wiki/TurritellaThe "turritella agate" is a misnomer because the snails in the mix are not turritella, they are goniobasis. Just an interesting rock fact!
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Thunder69
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Post by Thunder69 on Mar 27, 2014 10:21:17 GMT -5
John those are some nice Goniotella Slabs...Nice orientation too...JOhn
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Post by beefjello on Mar 27, 2014 19:30:31 GMT -5
Those are some terrific slabs John! As far as orientation goes you totally nailed the snails!
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Fossilman
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Post by Fossilman on Mar 28, 2014 13:54:03 GMT -5
Nice cuts!
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Post by Bluesky78987 on Mar 28, 2014 15:29:06 GMT -5
Awesome. Let's see some cabs now. Great stuff.
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Post by 150FromFundy on Mar 28, 2014 16:35:53 GMT -5
Most of the hard Turritella that I have worked with has the dark black matrix. Whenever I ran into the lighter matrix, the rock always got soft and porous and did not work well. Your matrix looks reddish-brown. Does it appear solid, or will you have to stabilize?
Darryl.
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herchenx
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Snails!
Mar 28, 2014 17:03:13 GMT -5
Post by herchenx on Mar 28, 2014 17:03:13 GMT -5
the light may be a little deceiving, but it is very dark and very solid.
Part of the color is the red oil from the crazy lace I had cut previously. The last photo is the truest color of the 3.
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tkvancil
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Post by tkvancil on Mar 29, 2014 0:21:22 GMT -5
Love that stuff. Nice looking slabs.
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jamesp
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Post by jamesp on Mar 29, 2014 6:18:21 GMT -5
The way they settled makes good sense. Sure makes a fine pattern when most are cut through the length.
You are fortunate to have 3-6 " plates to cut such fine slabs from.
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Post by Donnie's Rocky Treasures on Mar 29, 2014 7:26:57 GMT -5
Yep, I agree, that's some good looking slabs ya got there!
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Deleted
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Post by Deleted on Mar 31, 2014 21:20:32 GMT -5
I happen to have a couple of very nice pieces from John. I am not almost finished with a core drill pres. Waiting for dry weather and a free day to collide so I can finish and can get to sphering it. Cant wait!
Nice work John!
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herchenx
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Snails!
Mar 31, 2014 21:35:56 GMT -5
Post by herchenx on Mar 31, 2014 21:35:56 GMT -5
Can't wait to see those Scott!
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39don
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Post by 39don on Mar 31, 2014 21:38:10 GMT -5
Super nice slabs John. You ACED the orientation for sure!!!!!!!!!!
I'm generally not so lucky but slabbed some recently that had a blue tint in the shells insides. The blue also contained a multitude of fractures.......Bummer!!!!!!!!!!!!
39don
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herchenx
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Snails!
Mar 31, 2014 22:02:18 GMT -5
Post by herchenx on Mar 31, 2014 22:02:18 GMT -5
39don that tint would be cool to see, did I miss your post or did you not post it?
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