RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 13, 2021 14:10:25 GMT -5
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Brian
fully equipped rock polisher
Member since July 2020
Posts: 1,512
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Post by Brian on Feb 13, 2021 14:30:23 GMT -5
That one looks like an everything bagel! Do you notice much difference in the interiors between the flatter ones vs the more rounded ones? brian I think I can't discern as much difference between shapes as I can sizes. I've noticed the most vibrant colors and patterns tend to occur in specimens smaller than a cantaloupe. Any bigger and they seem to be more amorphous on average. Prominent agate veins running through them seems to stack the odds in favor of awesomeness too. These veins are often prominent on the outer surfaces because they weather slower than the rest of the stone. Let me see if I can find a good example ... stay tuned. Thanks, Randy! Those examples are great! It seems counterintuitive to me that the smaller samples would be more interesting as I would think it would take a longer time for the larger ones to fossilize which could lead to more variation as the environment changed. Do you think the composition of the poop could affect the patterns? For example, if smaller dinosaurs ate different plants, the minerals present in their poop could differ from the poop of larger dinos that had a different diet.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 13, 2021 16:43:06 GMT -5
brian interesting thoughts there. I'll share what I believe, which by the way is pure speculation. I suspect that the variation of colors is mostly from different absorption tendencies of the various fragments within a coprolite. I think the various plant materials did not hardly contribute to the colors, but rather varied in their rates of absorption of surrounding minerals adjacent to the turd. I've noticed that many of the colors seem to indicate iron oxides and manganese also. I'm reluctant to believe the plant material held enough of those minerals to produce the colors we see. I believe the density of the turd fragments varied according to what the plant originally was and the final degree of reduction each fragment received from the digestion process. We know that even today the variation of digestion of plant material varies tremendously and I've found evidence it was the same for these dinos. Here's some photos of tough twig cross sections that did not get digested enough to destroy their identity. The twigs are about pinky diameter.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 13, 2021 16:43:24 GMT -5
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 13, 2021 16:46:14 GMT -5
I believe the three twig cross sections in the above photo were harder, tougher than the surrounding matrix and thus absorbed color agents at a different rate.
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Post by 1dave on Feb 14, 2021 13:33:41 GMT -5
brian I think I can't discern as much difference between shapes as I can sizes. I've noticed the most vibrant colors and patterns tend to occur in specimens smaller than a cantaloupe. Any bigger and they seem to be more amorphous on average. Prominent agate veins running through them seems to stack the odds in favor of awesomeness too. These veins are often prominent on the outer surfaces because they weather slower than the rest of the stone. Let me see if I can find a good example ... stay tuned. Thanks, Randy! Those examples are great! It seems counterintuitive to me that the smaller samples would be more interesting as I would think it would take a longer time for the larger ones to fossilize which could lead to more variation as the environment changed. Do you think the composition of the poop could affect the patterns? For example, if smaller dinosaurs ate different plants, the minerals present in their poop could differ from the poop of larger dinos that had a different diet. IMO the drying out that created the openings occurred within weeks and months. FILLING those voids occurred many millions of years later. 225 million years ago an unusual mineral assembly colored the wood in Arizona's Petrified Forest - - - BUT that same mineral collection was in play in Utah at the same time!
This is just an almost ordinary agate vein in the area of Silver Reef - that extends into St. George Utah.
forum.rocktumblinghobby.com/post/661812/thread
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Brian
fully equipped rock polisher
Member since July 2020
Posts: 1,512
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Post by Brian on Feb 14, 2021 15:10:10 GMT -5
Thanks for chiming in, 1dave! It makes sense that the drying process is a blink of the eye in the grand scheme of things.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 16, 2021 9:01:40 GMT -5
TURD TUESDAY
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rocket
spending too much on rocks
Quality slabs for quality cabs in 2022
Member since September 2020
Posts: 292
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Post by rocket on Feb 16, 2021 13:01:48 GMT -5
Thanks Randy for the bonus slabs...I finally get to play on turd Tuesday...
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Post by jasoninsd on Feb 16, 2021 15:16:34 GMT -5
Thanks Randy for the bonus slabs...I finally get to play on turd Tuesday... Thanks for posting these!!! I've been looking around and there really aren't a lot of pics of poop cabs! Once the weather gets a little more conducive to running the wet saws, I'll be slabbing some crap to do the same as you!
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 16, 2021 17:26:17 GMT -5
Thanks Randy for the bonus slabs...I finally get to play on turd Tuesday... Goodness! Those look great and thanks for posting them. Everyone ought to have a coprolite cab!
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Post by stephan on Feb 16, 2021 18:52:43 GMT -5
Maybe? DSC_2833_Turd Tuesday by Stephan T., on Flickr One of the drawbacks of buying up uncurated estates. You sometimes have to guess. From a purchase 10 years ago. Found it at the bottom of a crate. For the most part, it looks like jasper, but some of those black structures seem to suggest the circular-ish structures, with patterns that could be wood grain, of undigested twigs seen in some of RWA3006 's posts. Maybe more rotted? Maybe coincidence. Wish I knew its origin, but the original owner apparently hounded "all over the West in the 50s and 60s" and also had a few pieces of bone.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 16, 2021 23:13:11 GMT -5
Thanks for showing that stephan It certainly has an appearance that hints at coprolite doesn't it. One thing I've noticed about buying estate rocks from southern Utah is if a collection has either bone or coprolite, it often has the other also in the hoard. It would be nice if we had the provenance of so many more pieces.
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Post by stephan on Feb 16, 2021 23:25:15 GMT -5
RWA3006 : provenance would be wonderful to know. All I can say is that there was a bunch of stuff, mostly from CA, but elsewhere also: Assorted unknown brecciated jaspers, assorted agates, MHPJ, Stone Canyon, silver lace onyx, variscite... whale bone, and a few bits of Dino bone, and a ton of unknown stuff.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 19, 2021 9:48:04 GMT -5
Here's a pretty one.
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Post by rockjunquie on Feb 19, 2021 10:35:25 GMT -5
Here's a pretty one.
Kinda looks like it has some dendrites. Do you find dendrites in poo?
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 19, 2021 10:40:48 GMT -5
Yes, rockjunquie I've found them a number of times. I ought to go browse through some and see if I can find some to share.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 19, 2021 10:50:27 GMT -5
Here's one with dendrites.
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RWA3006
Cave Dweller
Member since March 2009
Posts: 4,578
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Post by RWA3006 on Feb 19, 2021 10:51:01 GMT -5
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Post by rockjunquie on Feb 19, 2021 10:51:54 GMT -5
Here's one with dendrites.
There ya go! Do you think those are dendrites in the one I commented on or something else?
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