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Rubykicks

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Found this at the Monroe Reservoir in Indiana on Monday. Looks like a brachiopod made of pyrite?  Or is it more likely a cast?  

20210511_163335.jpg

20210511_163425.jpg

Edited by Rubykicks
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Looks like pyrite replacement, to me. 

May be a brachiopod, or a bivalve. 
 

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16 minutes ago, Rubykicks said:

brachiopod made of pyrite?  Or is it more likely a cast?

Replacement is like both. The shell just kind of gets bumped out by minerals during fossilization.

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3 minutes ago, Fossildude19 said:

Looks like pyrite replacement, to me. 

May be a brachiopod, or a bivalve. 
 

So it's in a larger chuck of rock. What would your advice be for getting it out? Or would you just leave it so as not to damage it?  I'm sure it's not uncommon or special, but I would like to keep it for my collection. :)

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If the rock is large or unwieldy you could perhaps use a tile saw to trim it down.  If by "get it out" you mean to remove it entirely from the matrix, I think it is far too fragile for that.  Also it looks nicer against the matrix than it would on it's own, in my opinion.

 

Don

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2 minutes ago, Rubykicks said:

So it's in a larger chuck of rock. What would your advice be for getting it out? Or would you just leave it so as not to damage it?  I'm sure it's not uncommon or special, but I would like to keep it for my collection. :)

I think its going to be stuck onto the rock forever. Its probably neither feasible nor advisable to separate it from the matrix. You could cut the surrounding rock down to a more manageable size using a tile saw. Keep in mind that pyrite is transitional, it will eventually "rust" or oxidize away. Pyrite is formed under reducing conditions, but once it is surfaced, it is introduced to oxidizing conditions which will initiate its degradation. One thing you can do to slow that down is to coat it, protecting it from oxygen in the air. Paraloid/acryloid B-72 is the preferred coating but I'm sure others are available.  

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And you should know that the shock of a hammer blow elsewhere on the piece can dislodge fragments in a most disappointing way.

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