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Strange rock, fairly heavy, I hammered it and broke then submerged in vinegar. There was a reaction. Found in Colorado

+1 vote

asked Sep 29, 2018 by Ryan936walker (160 points)

3 Answers

0 votes
Why would you hammer a specimen? You destroy so many things which could help identify the specimen. Are you saying this was one rock and you broke it into twenty pieces?

So, if part of this reacted with vinegar it could be limestone or calcium carbonate or calcite or a hundred different compounds. I see what could be metal, I see what could be clay. It is just really hard to say. I see people crushing rocks on the beach to try to identify the rock and I just wonder why.

A metal would be significantly heavier than a rock of the same size. The rock looks like it cooled slowly under ground because you cannot see large grains. Some of the rock looks like some silt leeched into the rock bearing sand which was compressed and turned into rock.

The truth of the matter is many rocks are igneous. Formed by heat of volcanic action and the like. Some igneous rocks cool rapidly on the surface of the earth, some slowly under ground. Some form when mineral solutions leak into porous rock. That rock gets broken down by weathering effects get dragged along by glaciers and dropped in alluvial flows which then solidify in concretions. Many rocks are conglomerations of these different actions and crushing them obliterates things which could help identify at least some of the characteristics.
answered Oct 1, 2018 by Weasel (58,850 points)
The exterior before looked like the bottom picture. It was dinosaur claw shaped and the underside was coated with thick layer of dirt and not as smooth. Sorry I don’t have earlier pics. I was impatient and wanted to see the interior. Too many different minerals and rock types to verify
0 votes
Well that last one looks like basalt with quartz filling in the small fissures.
answered Oct 2, 2018 by Weasel (58,850 points)
0 votes
To me, it looks like basalt, but the brown parts do look like part of a fossil... If that is the case, perhaps some sort of metamorphic blend of basalt and shale. As for breaking it, everybody gets caught up in the moment sometimes, but in the future, don't go swinging a hammer at every rock you see, no matter how tempting it is. Always stop and think about what you are doing first. :)
answered Oct 5, 2018 by linkisnotzelda (5,370 points)