|
Post by knave on Oct 18, 2021 0:01:20 GMT -5
Labeled “Mexican Azurite” nice dark color, some tiny azurite crystals, some bits of malachite. But what is the matrix, grinds like quartz almost. Rock has a good weight. I’ve got a good bit of this material and want to know the matrix. ETA: THANKS in advance!!
|
|
|
Post by knave on Oct 18, 2021 0:01:44 GMT -5
DRY
|
|
|
Post by hummingbirdstones on Oct 18, 2021 10:26:48 GMT -5
Evan, here's some info from mindat.org: link
Hope that helps a bit.
|
|
|
Post by knave on Oct 18, 2021 10:33:19 GMT -5
Thank you robin!!
|
|
|
Post by knave on Oct 18, 2021 10:33:35 GMT -5
Host rocks are volcaniclastic from the Jurassic Henrietta formation and the Laramide Mesa formation in which monzonitic to quartz monzonitic stocks intrude. The sericitically altered stocks and the intruding volcaniclastic rocks host the main copper mineralization.
|
|
|
Post by knave on Oct 18, 2021 10:40:47 GMT -5
mon·zo·nite /ˈmänzəˌnīt/ Learn to pronounce nounGEOLOGY a granular igneous rock with a composition intermediate between syenite and diorite, containing approximately equal amounts of orthoclase and plagioclase.
|
|
|
Post by rockjunquie on Oct 18, 2021 10:48:52 GMT -5
Host rocks are volcaniclastic from the Jurassic Henrietta formation and the Laramide Mesa formation in which monzonitic to quartz monzonitic stocks intrude. The sericitically altered stocks and the intruding volcaniclastic rocks host the main copper mineralization. THAT was a mouthful!
|
|
|
Post by knave on Oct 18, 2021 10:53:58 GMT -5
True but very helpful. My matrix is likely feldspar to feldspar/quartz.
|
|
|
Post by mohs on Oct 18, 2021 11:19:24 GMT -5
A good question Ev sounds like you have a good idea My amateur write up follows wish you were here ! Maybe you'll come out to Quartzite and visit fingers crossed As just a throw out suggestion from a picture Its look a fine grained rhyloyte I’m working that chys pile It’s a dynamited excavated hill of rock The host rock of this copperish oxides are all over the place ! Some of it is felsic fine-grained light color. which I take to be rhyolyte Also have azurite on a mafic dark green rock That rock as larger crystals embedded within I take to be pyroxene or hornblende ? Unfortunately 99% of this huge pile of rock is not of lapidary grade. Very weathered Most the copper oxide is surface only Butte I enjoy working amongst the colors and trying to determine type Somewhere in that pile is a gem There a lot of great you tube geology lectures Now that I’ve got lots of time been availing myself of the free education
|
|
|
Post by rockjunquie on Oct 18, 2021 11:22:45 GMT -5
I was gonna suggest dolomite, but, apparently, I'd be wrong.
|
|
|
Post by mohs on Oct 18, 2021 11:30:07 GMT -5
like that dude say geology does not like to be put in box of our concepts gradation of grains
|
|
|
Post by mohs on Oct 19, 2021 16:31:17 GMT -5
this is interesting stuff now I'm wondering if some my chrys is in a monhzonite quartzone ?
have you cut into that matrix Ev? see what the inside matrix grains are like ...
|
|
|
Post by knave on Oct 19, 2021 16:39:29 GMT -5
Yes I have cut into it. It is much the same. A fraction softer than quartz. But not grainy like quartzite. White streak. Pic tonight
|
|
|
Post by hummingbirdstones on Oct 19, 2021 21:33:24 GMT -5
Host rocks are volcaniclastic from the Jurassic Henrietta formation and the Laramide Mesa formation in which monzonitic to quartz monzonitic stocks intrude. The sericitically altered stocks and the intruding volcaniclastic rocks host the main copper mineralization. THAT was a mouthful! Boy, you're not kidding! My first thought after reading it once was: "Huh?"
|
|
|
Post by knave on Oct 20, 2021 7:45:52 GMT -5
mohs this is a little piece that’s through 80 grit as a tester. It’s dry. Well maybe some palm sweat
|
|
|
Post by mohs on Oct 20, 2021 8:43:03 GMT -5
boiler room rock !
|
|
|
Post by knave on Oct 20, 2021 9:01:33 GMT -5
this is my worry stone for the day I can hold it while I’m on hold with Wally World
|
|
|
Post by stephan on Oct 22, 2021 0:37:18 GMT -5
Cool stuff. It looks like it polishes quite decently. Given that azurite is pretty soft (3-4), did it have undercutting issues?
|
|
fuss
spending too much on rocks
Member since October 2018
Posts: 250
|
Post by fuss on Oct 22, 2021 6:05:38 GMT -5
Your matrix does not look like a Monzonite from the images, more likely a sedimentary rock. If you can get any close up shots of the rock especially a fresh interior that would be helpful, or if you have a loupe or any kind of magnification have a close look and describe what you see. Monzonite is a relatively rare rock type and can be difficult to ID since really its all about percentages of Q, A and P and measuring those requires a thin section to be cut and sent to get analyzed...see here www.sandatlas.org/monzonite/
|
|