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Help with crystal specimen I found in coastal cliff please


#1

I have found a nice crystal agate geode ( I think)… but maybe I’m wrong it’s just very different looking then the usual agate/chalcedony/Carnelian I find while at the beach hopefully someone can help me identify.
The single crystals are what fell off the rock while I was getting it out the clay Cliff.
I have found palaeocene age bull shark teeth around same area just in case that’s any help , thanks.


#2

Two more photos


#3

Hello … I have seen some material like this come into my lab for analysis and valuation from a mine in Nicaragua. The reddish material looks like non-precious Jasper Opal and the white material looks like non-precious Milk Opal. I have seen this in shades of yellow and peanut butter brown as well. Weigh a piece of it dry. Then soak it in water for 15 minutes, blot it dry and weigh it again. Non-precious opal will absorb water readily and weigh a lot more after wetting. They can even change color intensity. You will even see them getting heavier when trying to take a SG measurement! A good SG measurement can help you confirm it is opal (especially if it gets heavier while you are measuring the SG). SG of non-precious opal is 2.15 +0.08 - 0.90. Most of the red and brown non-precious opal will be opaque, but the milk opal will be semi-translucent. Hope this helps. Good luck. Michael at The Diamond Grader in Las Vegas. :smiley: