What is this rock I found, it's got little glittering things on it.

I found this in Sussex county New Jersey, it was used to line my driveway with a bunch of other rocks, other than that I don't know where it actually came from if not originally from there. I don't know about the hardness, or the other parameters suggested in the ID guide, I haven't really tried to break it apart or anything.

I am considering smashing it with a hammer, but I like the way it exists now.


rock 1

enter image description here


closed as unclear what you're asking by Gimelist, Fred, Jan Doggen, daniel.neumann, Semidiurnal Simon Nov 12 '18 at 11:28

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ "I don't know about the hardness,or any of the other parameters suggested in the ID guide". There's a reason those things are listed in the ID guide. It's because that is the information that people will need to ID the rock. If you refuse to provide them, then people can't answer! Voting to close this question for now. $\endgroup$ – Semidiurnal Simon Nov 12 '18 at 11:28
  • $\begingroup$ i completely understand, and take your concerns seriously, however as i am an admitted dilettante, i find person27's response and Chayan Lahiri confirmation completely satisfactory, and as disappointing to the; community, guidelines, and intent of this website, as it may be i will probably not pursue any further information. i may get around to fulfilling your criteria but this Big O notation stuff is driving me nuts and i should really be focusing on that. $\endgroup$ – buggs Nov 14 '18 at 23:11

This is a vug (also called a pocket) of chalcedony, which is a variety of quartz. The bed of sparkling crystals is known as a druzy (of quartz, variety chalcedony). This rock looks like it had numerous gas bubbles in it at one time that were lined with chalcedony by precipitation when it formed. That means you'll be disappointed if you cut it in half because there will be no more crystals than you see on the exterior.

  • $\begingroup$ I think its Chalcedony too. $\endgroup$ – Chayan Lahiri Nov 11 '18 at 21:37
  • $\begingroup$ You're welcome :) I'd say the locality is probably right since it probably came from a local quarry. Chalcedony can be found all over the world. $\endgroup$ – person27 Nov 11 '18 at 22:53

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