|
Post by scienceteacher79 on Mar 19, 2021 16:58:51 GMT -5
Please help ID the rocks in the photos below. My guesses were based on my trim saw's ability to cut through the rock. I believe the marble to be correct, but the black and green rocks stump me. I know I do not think I have black jade based on a simple light test. Any suggestions or corrections are most welcome. Thanks in advance for taking a look and responding. None are magnetic.
|
|
|
Post by rockjunquie on Mar 20, 2021 7:42:01 GMT -5
That green spotted one is really cool. Can't help with IDs but it looks like you have a good handle on them.
|
|
Fossilman
Cave Dweller
Member since January 2009
Posts: 20,681
|
Post by Fossilman on Mar 20, 2021 10:00:31 GMT -5
The black one looks like Obsidian..
|
|
herb
spending too much on rocks
Member since November 2011
Posts: 444
|
Post by herb on Mar 20, 2021 10:02:37 GMT -5
The 3rd individual shot looks like obsidian to me. That's the extent of my identification skills!
|
|
|
Post by scienceteacher79 on Mar 20, 2021 10:48:49 GMT -5
I am sure that the black ones aren't obsidian as I have found that too. The black ones aren't glassy enough, but thanks for taking a look.
|
|
fuss
spending too much on rocks
Member since October 2018
Posts: 250
|
Post by fuss on Mar 20, 2021 11:30:19 GMT -5
where did you collect these from Idaho? The suspected marble can be tested with some strong vinegar or dilute hcl(preferred). Have you tried doing a hardness scratch test on any of them? I think you are right about the porphyritic one though it could also be a basalt porphyry.
|
|
fuss
spending too much on rocks
Member since October 2018
Posts: 250
|
Post by fuss on Mar 20, 2021 11:31:31 GMT -5
meant to say where "IN" Idaho were they collected.
|
|
|
Post by scienceteacher79 on Mar 20, 2021 12:38:37 GMT -5
meant to say where "IN" Idaho were they collected. Snake River in Southern Idaho. White has to be marble as it is softer but takes a nice shine. I did try vinegar, no reaction. Don't have HCl to try. Hardness is about a 5. Black rocks scratch the white ones. Green rock is the hardest...7-8.
|
|
|
Post by As I in does tries! on Mar 22, 2021 21:09:56 GMT -5
Greetings and welcome form Scotland, my guess for the black stone is Chalcedony or Basalt, if it was black and white in the same stone then it would be Onyx.
|
|
|
Post by stephan on Mar 23, 2021 18:20:49 GMT -5
#3 "Unknown" looks like jasper or chert. If that's the one you're calling the "green rock" the hardness fits, too.
|
|