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2,235 questions

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What type of rock is this? I’m having trouble figuring it out. Thanks.

0 votes

asked Apr 20, 2018 by Athena R (120 points)

2 Answers

0 votes
Okay, there are a significant number of questions but let me start with this. This sample is one with a stone inside another substance. So there are two substances here. The yellow substance. How hard is it? Well, you can't tell from a picture, so I would encourage you to try to scratch some yellow off. If it scratches easily and flakes off it could be a soft metal, like gold. If it is hard and you cannot get the substance to scratch, it could be quartz, diamond, citrine, topaz. If it is softer material and not gold it could be sulphuric, it could be flourite. It could be pyrite. Pyrite would be magnetic, gold would not.

The outside(husk) might be rhyolite, a volcanic rock. It is porous enough to allow elements and compounds in solution to permeate the husk and fill in voids. The resulting crystals are formed inside the host rock. Due to erosion and earth movement and weathering the rock inside gets exposed.
answered Apr 23, 2018 by Weasel (58,940 points)
0 votes
It's hard to tell such a crystal without more information. It does have an appearance of oxidized pyrite. Does it have a black streak? That would be a good indicator of it being pyrite.
answered Apr 27, 2018 by hershel (52,800 points)