Bronzviking Posted May 28, 2018 Share Posted May 28, 2018 Hi all, I took my Mom to lunch at Frenchy's Dunedin, Florida and than took a walk on the Causeway. I found this unusual piece that I was going to toss but kept it. It is about 3" by 2" by 2" and looks like granulated brown sugar with crystals (I think sandstone) under the eye loop. It appears to have about 4 shell casts on top with some of the seashell still embedded in the layers. On top it looks like a turtle with its head sticking out?? There is a dozen or more shell molds or imprints all over this conglomerate of sediment. What do you think of this find? Is it considered a fossil? Thanks in advance! 1 Link to comment Share on other sites More sharing options...
Bronzviking Posted May 28, 2018 Author Share Posted May 28, 2018 Here's 3 more pics of same piece. 1 Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 28, 2018 Share Posted May 28, 2018 Yes, it is a bivalve coquina. Lots of fossil shells compacted together. https://en.wikipedia.org/wiki/Coquina Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Bronzviking Posted June 4, 2018 Author Share Posted June 4, 2018 Hi T Dad, It said they are common on the East Coast and I found this on the West Coast. I looked at the pictures and mine don't look anything like these shells glued together with sediment?? 1 Link to comment Share on other sites More sharing options...
ynot Posted June 4, 2018 Share Posted June 4, 2018 51 minutes ago, Bronzviking said: It said they are common on the East Coast and I found this on the West Coast. I looked at the pictures and mine don't look anything like these shells glued together with sediment?? Coquina is a common sedimentary rock type which can be found in many places around the world. They can have very different shells and cementing agents that make up the coquina, giving different appearences. 1 Darwin said: " Man sprang from monkeys." Will Rogers said: " Some of them didn't spring far enough." My Fossil collection - My Mineral collection My favorite thread on TFF. Link to comment Share on other sites More sharing options...
Rockwood Posted June 4, 2018 Share Posted June 4, 2018 Careful ! There is a percentage limit on amount of matrix allowed for it to be true coquina. I remember trying for an appeal one time. 2 Link to comment Share on other sites More sharing options...
Plantguy Posted June 5, 2018 Share Posted June 5, 2018 I like looking at Florida rocks and wondering about how they got that way--thanks for your photos! Your sample looks awful sandy to me which makes me want to call it a highly fossiliferous sandstone rather than a coquina...Been too long since I took a petrology class but since moving to Florida I have used Coquina when describing mostly shells/fragments that are cemented together and rather porous. Before I moved here I probably would have called it coquina too. Maybe its a sandy coquina...might be just splitting hairs here on the definition... Regards, Chris Link to comment Share on other sites More sharing options...
Bronzviking Posted June 5, 2018 Author Share Posted June 5, 2018 Thanks Chris for looking and taking the time to ID! I agree with you that it is highly fossiliferous sandstone. It is very rough to the touch, like sandpaper and has a mustardy yellow color unlike all the limestone fossils in this area. 1 Link to comment Share on other sites More sharing options...
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