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Author Topic: Can you help me ID these rocks?  (Read 1841 times)

Offline DutchGuy

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Can you help me ID these rocks?
« on: 17/08/2015 09:18:28 »
The first one i got from a friend. He doesnt know what it is, and i dont know either. All i know: its large, greenish and as a lot of Coral/polyp-like extensions:


The other one: could it be pegmatite? I found it in Scotland in 2007. Its about 10x10 cm (round):


 

Online Bill S

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Re: Can you help me ID these rocks?
« Reply #1 on: 17/09/2015 22:37:56 »
How hard is the first specimen?  Here’s Mohs scale if you are not already familiar with it.

https://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness

You could be right about the second one.  If you don’t mind risking damaging it, it would be worth trying to see how easily the different parts could be separated.

There is a dark patch at about “five o clock” on 2 that looks a bit like botryoidal haematite. If you scratch it, does it give a red streak?
 

Offline Atomic-S

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Re: Can you help me ID these rocks?
« Reply #2 on: 18/09/2015 06:47:16 »
Greater magnification would help, particularly with the coral-like specimen.
 

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Re: Can you help me ID these rocks?
« Reply #2 on: 18/09/2015 06:47:16 »

 

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