Found these today while collecting fossils. I would love to know what they are if Anyone can identify them! Thanks
These are either:
- fragments of a bivalve shell (thick ones show the prismatic structure of the main layer)
- fragments of a vein (they often have a prismatic crystalline structure due to the crystals growing as the vein gradually opened, rather than infilling an open cavity)
In this case it is a bivalve shell, possibly one with little surface ornamentation, such as Inoceramus.
Here's a larger example
- http://www.oceansofkansas.com/images2/prisms.jpg (I can't find the page that came from)
Here's anothe example (including a pearl)
And if you scroll down this page a bit, you'll see an annotated photograph showing the prismatic layer and the other layers (nacreous layer and periostracum)
The nacreous layer is what gives the mother-of-pearl effect on some shells, such as abalone.
That layer is remarkable stuff... It is said to be '3,000 times more break-resistant than the mineral that comprises its building blocks, aragonite', 'Close up, the shell resembles a brick wall, with ...Organic mortar'