Jump to content

Need Help Identifying This Rock I Found Today.


Recommended Posts


Not an easy one to ID there. Being wet (and oxidized outside?) isn't helping either. I don't know what this one is.

I'd lean towards some ultramafic igneous rock like peridotite or pyroxenite. Could be some metamorphism happening there too making it harder, or something like an igneous intrusion in metamorphics. The crystals being either peridot or diopside, respectively if peridote or pyroxenite. But the color is kinda off for both of those, so dunno. Beryl can be that color, but it doesn't seem like a hostrock for beryl, so...

A scratch test on the crystals might help narrow things down. So would the local geology. But that looks like one that easier to ID in hand with magnifier loupe than via picture. So unless anyone else recognizes it as a local rock, might be one to take to a geologist to ID. 

  • Like 2
Link to comment
Share on other sites

Hard to tell from the picture. The surface looks polished or 'slickenside' like what you might find in a fault zone. There also appears what might be a somewhat flattened orientation in the broken surface in the first picture. I have some similar looking samples that were boudins in serpentinized ultramafic dikes in Franciscan fm which is most likely the local rocks in your area.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...