GeologyRocksCool rock with crystals inside of its crevices?
- Login to post a new forum topic.
Rank:
Contact:
From your pictures I would
Sun, 03/23/2014 - 16:07From your pictures I would say that you have quartz crystals there in a vug (a vug is a cavity within a rock, usually crystal lined.)
It could be calcite which look similar, and a quick check would be to try scratching a crystal with a piece of copper.
If it leaves a whitish streak it is almost certainly calcite, and you will need to do an acid test to confirm. I believe in the States you can still buy acid (Health & Safety won't allow it over here), but probably the smallest quantity you can buy will be a pint. You really don't need a pint of neat hydrochloric acid (unless you have VERY blocked drains), because you are going to use one drip - and then it will be diluted to 5% HCl.
Why not take it to the local school/college and ask the science teacher to test it for effervesce with the application of weak acid.
If it is quartz you will leave a bit of the coper behind. This needs testing with a good steel blade. If even then if it is difficult to scratch or when you look closely it leaves a grey deposit behind, you have certainly got quartz (the grey deposit is the steel from the blade!)
Let us know how you get on please. My reckoning is quartz.
John
“Civilisation exists by geological consent, subject to change without notice.” - Will Durant
Rank:
Contact:
That's what I thought, but
Mon, 03/24/2014 - 21:18That's what I thought, but often people wash them just prior to taking the photo, and the pic is just too far away to acuratly determine the crystal shape.
John
“Civilisation exists by geological consent, subject to change without notice.” - Will Durant
Rank:
Contact:
Cool rock with crystals inside of its crevices?
Submitted by nofxroxx on Fri, 03/21/2014 - 04:00.Hi guys. I was on vacation last year in New Buffalo, Michigan. My family and I always rent Houses on the beach. I was walking around the beach and found this big rock. It's about 10 pounds light grey with some white streaks/spots. Now, the interesting thing is that it has a few crevices with "chunky" crystal-like things on it. There's a few of these crevices too. Iv'e been searching for what kind of rock this is, but can't seem to find out. It's hard to see in the pictures, but there are sparkly crystals in the crevices
can anyone help? ps. tried to upload the pics within the forum but it wasn't working. sorry! here are all the links to the pictures.
http://tinypic.com/r/23st6xt/8
http://tinypic.com/r/16h2ogj/8
http://tinypic.com/r/xdwll0/8
http://tinypic.com/r/qwx3sg/8