More Finds, Better Pictures, Threw Out Most of the Matrix

[JonUte]

Hi, Everyone!  A belated Merry Christmas and best wishes for the New Year.  It’s warm and intermittently sunny in Venice, Florida so it’s beach time.  Here are some new finds and better pictures of some old finds.  I still have no idea what these things are.

[JonUte]

And this one that never made sense to anyone:

[JonUte]

And this one:

[JonUte]

This looks like a chunk of fossilized bone with predation marks.  But then, they did legalize weed at the VA…

[JonUte]

This one made me curious.  Really curious.

[JonUte]

As always, thank you very much for you responses.

 

Jon

[Baking Geologist]

Just looking at them the dark color is throwing me.  My first guess is basalt, but these are from Florida 🤷‍♀️

[ClearLake]

3 minutes ago, Baking Geologist said:

 My first guess is basalt, but these are from Florida

Phosphatic pieces are more likely as they are very common along the SE USA beaches. And many of them contain imprints of fossils. 

[Baking Geologist]

Just now, ClearLake said:

Phosphatic pieces are more likely as they are very common along the SE USA beaches. And many of them contain imprints of fossils. 

Ah! I forget about phosphates.  That makes sense.  

[Brandy Cole]

Fourth item is a chunk of rib bone.  The rest look most similar to chunks of mineralized turtle shell to me.

 

That said, Florida isn't my area. Other experts from there may weigh in.

[JonUte]

19 hours ago, Brandy Cole said:

Fourth item is a chunk of rib bone.  The rest look most similar to chunks of mineralized turtle shell to me.

 

That said, Florida isn't my area. Other experts from there may weigh in.

I’d see turtle shell referenced before regarding similar pieces, excepting the rib bone (thanks).  These specimens have a too many defined  layers to be explained away as phosphates.  

 

20 hours ago, Baking Geologist said:

Just looking at them the dark color is throwing me.  My first guess is basalt, but these are from Florida 🤷‍♀️

Most beach finds in my neighborhood are black or brown.  I’ve learned through trial and error to sort out the phosphatic matrix from the fossils, such as alligator scutes, ray scutes and turtle shell pieces, which all tend to be black here.

[ClearLake]

17 hours ago, JonUte said:

These specimens have a too many defined  layers to be explained away as phosphates.  

You probably should not try "to explain any of them away as phosphates" as phosphatic fossils are quite common in many areas (especially Florida).  Phosphate is a mineral (or perhaps more correctly, a group of minerals) and sometimes fossils are composed of it and sometimes there is phosphatic rock with fossils in it, and sometimes there is just phosphatic rock without any fossils.  The interesting feature (or annoying, depending on how you want to look at it) is that what we often refer to as "phosphatic nodules" here on TFF are just chunks of phosphate that have formed or eroded into very interesting shapes (but are not fossils).  Several of the pieces you posted are very likely fossils of one sort of another, a couple appear to be bone fragments and some (I believe) are just non-fossiliferous phosphatic nodules with interesting shapes or too small or non-diagnostic to say for sure one way or the other.

 

There was an interesting thread here some time ago on phosphatic fossils: https://www.thefossilforum.com/topic/5348-show-us-your-phosphate-fossils/

 

 

Edited December 29, 2023 by ClearLake
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[Harry Pristis]

31 minutes ago, ClearLake said:

Several of the pieces you posted are very likely fossils of one sort of another, a couple appear to be bone fragments and some (I believe) are just non-fossiliferous phosphatic nodules with interesting shapes or too small or non-diagnostic to say for sure one way of the other.

 

There was an interesting thread here some time ago on phosphatic fossils: https://www.thefossilforum.com/topic/5348-show-us-your-phosphate-fossils/

I concur with ClearLake's assessment of the OP's finds.

That was an interesting thread about phosphate fossils.  That was 2009, before I learned the true nature of the fossilized twigs I was finding in North Florida.  I had assumed that the wood was silicified.  I found out that the petrified wood is REPLACED by a calcium phosphate mineral, fluorapatite.

 

Petrified wood from the river site in North Florida is mineralized with a calcium phosphate mineral as the hydroxyapatite variety, fluorapatite.  Mohs hardness 5 (similar to tooth enamel and obsidian).  Phosphatized wood is typically brown or black in color, while light color is consistent with silicification.

 

Analysis of the river specimens showed that the mineral composition is fluorapatite which commonly occurs as a detrital or diagenic mineral in sedimentary rocks. The dark color suggests that some relict organic matter is present.  Organic tissue was not evident in SEM [Scanning Electron Microscope] photos.

[JonUte]

For all of this information, I am in your debt.  I have learned so much in the past three months (that’s how long I’ve been doing this) and I continue to learn from each of you every day.

 

in short: Cool!