Please tell me this is not coquina

[BuddingPaleo]

Ok. I'm trying not to get too excited. Found this guy today. Looks like an entire oyster, barely cleaned it yet because I want to be fairly sure what I'm cleaning first. In florida, poking up in my yard. (Sand) please tell me it's not just interesting looking coquina. I really want it to be an oyster, like, I'm ready to name it I love it that much...

[Miocene_Mason]

looks to be an oyster. Coquina can have oysters in it, coquina is just compressed shell material. This doesn’t look like that though, a shell in some clay or some other unconsolidated sediment.

[Rockwood]

I think it's the remaining edge of a larger and thicker oyster that had been extensively bored by sponges.

Oh, by the way, this is not cquina. 

[abyssunder]

Coquina is a sedimetary rock which could be more or less cemented containing different kind of shells.
In this case, it has a nice oyster in it.

[Innocentx]

Very nice fossil!

[BuddingPaleo]

That makes my day. Thanks guys! I was so hoping I wasn't getting fooled. Now to figure out how to clean it! (Wasn't gonna bother if it wasn't) Adventure awaits!  

[Rockwood]

25 minutes ago, abyssunder said:

In this case, it has a nice oyster in it.

 

2 minutes ago, BuddingPaleo said:

Now to figure out how to clean it!

In it ? On it ? 

[BuddingPaleo]

28 minutes ago, Rockwood said:

I think it's the remaining edge of a larger and thicker oyster that had been extensively bored by sponges.

Oh, by the way, this is not cquina. 

Can you tell me how to tell the difference? Because I see the shell pattern often. Thought it was all coquina.

Also, I have a hard time taking pictures, but it's got a continuous line/lip running all the way round it, and one half of it has exposed round curve. I think there's a lot of it left.

[Rockwood]

5 minutes ago, BuddingPaleo said:

Can you tell me how to tell the difference? Because I see the shell pattern often. Thought it was all coquina.

Also, I have a hard time taking pictures, but it's got a continuous line/lip running all the way round it, and one half of it has exposed round curve. I think there's a lot of it left.

This is what the upper and lower surfaces would be. Everything between is oyster - borings.

[BuddingPaleo]

Awesome! Truly helpful. Thanks for illustrating!

[Plax]

oyster in limestone. Coquina can be a specific type of shell limestone with coquina shells dominating or in loose terms just shell marl or limestone. I'd do some googling to get the definitions of terms that folks are using to describe your finds.

[BuddingPaleo]

35 minutes ago, Plax said:

oyster in limestone. Coquina can be a specific type of shell limestone with coquina shells dominating or in loose terms just shell marl or limestone. I'd do some googling to get the definitions of terms that folks are using to describe your finds.

I've googled it, nothing I googled looks like a lot of what I've got, so since I'm *just* started and am trying to learn, I figured I would double check, because I'm obviously having trouble telling between the two. I have no one else to check with. 

[BuddingPaleo]

Also, when I googled oyster fossils, I got pictures of half shells...which did not help.

[Rockwood]

On 6/17/2018 at 6:37 PM, abyssunder said:

Coquina is a sedimetary rock which could be more or less cemented containing different kind of shells.
In this case, it has a nice oyster in it.

 

1 hour ago, Plax said:

oyster in limestone. Coquina can be a specific type of shell limestone with coquina shells dominating or in loose terms just shell marl or limestone. I'd do some googling to get the definitions of terms that folks are using to describe your finds.

 

1 hour ago, BuddingPaleo said:

so since I'm *just* started and am trying to learn,

There appears to be a bit of disagreement between two very learned folks here. Tells you something about the task ahead. 

[BuddingPaleo]

9 minutes ago, Rockwood said:

 

 

There appears to be a bit of disagreement between two very learned folks here. Tells you something about the task ahead. 

Yep! Windy road with no gps. Maybe I'm too old a pup, but I'm trying anyway! And appreciate all input.  I'll learn to recognize it before I die, because goals.  

[Rockwood]

38 minutes ago, BuddingPaleo said:

Yep! Windy road with no gps. Maybe I'm too old a pup, but I'm trying anyway! And appreciate all input.  I'll learn to recognize it before I die, because goals.  

Same here. 

[ynot]

From wikipedia....

Coquina (/koʊˈkiːnə/) is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates.[1][2] The term coquina comes from the Spanish word for "cockle" and "shellfish".[3]

For a sediment to be considered to be a coquina, the particles composing it should average 2 mm (0.079 in) or greater in size. Coquina can vary in hardness from poorly to moderately cemented. Incompletely consolidated and poorly-cemented coquinas are considered grainstones in the Dunham classification system for carbonate sedimentary rocks.[4] A well-cemented coquina is classified as a biosparite according to the Folk classification of sedimentary rocks.[5]

Coquinas accumulate in high-energy marine and lacustrine environments where currents and waves result in the vigorous winnowing, abrasion, fracturing, and sorting of the shells, which compose them. As a result, they typically exhibit well-developed bedding or cross-bedding, close packing, and good orientation of the shell fragments. The high-energy marine or lacustrine environments associated with coquinas include beaches, shallow submarine raised banks, swift tidal channels, and barrier bars.[5][6]

 

 

 

[BuddingPaleo]

5 minutes ago, ynot said:

From wikipedia....

Coquina (/koʊˈkiːnə/) is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates.[1][2] The term coquina comes from the Spanish word for "cockle" and "shellfish".[3]

For a sediment to be considered to be a coquina, the particles composing it should average 2 mm (0.079 in) or greater in size. Coquina can vary in hardness from poorly to moderately cemented. Incompletely consolidated and poorly-cemented coquinas are considered grainstones in the Dunham classification system for carbonate sedimentary rocks.[4] A well-cemented coquina is classified as a biosparite according to the Folk classification of sedimentary rocks.[5]

Coquinas accumulate in high-energy marine and lacustrine environments where currents and waves result in the vigorous winnowing, abrasion, fracturing, and sorting of the shells, which compose them. As a result, they typically exhibit well-developed bedding or cross-bedding, close packing, and good orientation of the shell fragments. The high-energy marine or lacustrine environments associated with coquinas include beaches, shallow submarine raised banks, swift tidal channels, and barrier bars.[5][6]

 

 

 

Ok, so are the shells always fragmented? I see so much that looks just like that oyster layering, which is why I wasn't sure. Can a whole lot of oysters compact to create those lacy layers, or should I look at them more closely? So confused. 

[ynot]

7 minutes ago, BuddingPaleo said:

are the shells always fragmented?

No.

7 minutes ago, BuddingPaleo said:

Can a whole lot of oysters compact to create those lacy layers,

Not likely.

8 minutes ago, BuddingPaleo said:

should I look at them more closely?

Never hurts to take a close look.

8 minutes ago, BuddingPaleo said:

So confused. 

Aren't We all?

[Miocene_Mason]

3 minutes ago, ynot said:

Aren't We all?

Would be no point in science if we weren’t.

[BuddingPaleo]

2 minutes ago, WhodamanHD said:

Would be no point in science if we weren’t.

Truth! 

[Rockwood]

1 hour ago, BuddingPaleo said:

Can a whole lot of oysters compact to create those lacy layers, or should I look at them more closely? So confused. 

Oysters are not shaped right to 'spoon' each other. Their layered look is a natural adaptation. For stabilization on soft bottoms I think.

Other bivalves can pile up to look much like a single organism though.

[FossilDAWG]

I suspect both valves are present, with a sediment filled gap between the upper and lower valves.

 

Don

[Rockwood]

1 minute ago, FossilDAWG said:

I suspect both valves are present, with a sediment filled gap between the upper and lower valves.

 

Don

Definitely. 

[BuddingPaleo]

12 minutes ago, FossilDAWG said:

I suspect both valves are present, with a sediment filled gap between the upper and lower valves.

 

Don

Oh, for sure. I've started cleaning some of the debris (Broken hand, slow going) Tonight I'm going to look up info on oyster beds/colonies. May be an oyster rave goin on out there.