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Post by gmitch067 on May 16, 2017 17:31:01 GMT -5
I obtained this small piece of a slab at the Consolidated Rock Shop here in Vacaville (they have a box dedicated to pieces of slabs - sort of a scrabble box) and need help in its ID. At first I thought it Obsidian, but when I got home found the word "green" penciled on its surface... and does show a dark green hue in direct light (Note the green color where I have sawed off and chipped away the edges with my dremel). My Mohs test kit (scratch pens with graduated hardness) results puts it in the range between 7-8 Mohs. It is too hard to produce any mark on either white or black streak plates. I am trying to produce a small pendant using dremel cutting/grinding, and hand sanding it down to polish it (also with a dremel). So far I have been able to smooth it down nicely using 220 - 2000 grit wet/dry silicon carbide sanding paper. BUT... the finer I sand it down the more I am noticing very small pitting appear. The close-up pics below were taken at the lowest power with an Opti-TekScope (Mod OT-M HDMI - 300X) - which shows the surface pitting (and unfortunately a flake I must go back to grind away). Sooo... 2 questions: Question-1: What is it? Question-2: How do I address the pitted surface when it comes to polishing - so it doesn't show the pits?
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Deleted
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Post by Deleted on May 16, 2017 19:25:36 GMT -5
You cut it. How hard/tough is it?
Looks like it may be jade. And the polish is an orange peel effect from polish.
Try diamond or tin oxide polish for jade.
Is it very hard and tough?
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Post by gmitch067 on May 16, 2017 20:02:20 GMT -5
Very hard. I had to change out the diamond saw in my dremel because I thought it wasn't cutting very well. (I later used that old blade on a 1/4" slab piece of ScriptStone Cobra Jasper and it buzzed through like a champ)
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Tommy
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Post by Tommy on May 16, 2017 20:07:43 GMT -5
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Post by gmitch067 on May 16, 2017 20:20:27 GMT -5
Wow! Totally cool! I have to go attack my garage and dig up my old reloading stuff... I have a powder scale there but I do not remember if it had a tare function (I know my food scale does, but it is a cumbersome beast... and tries to starve me occasionally). This will be an interesting project! Thank you!!
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Post by gmitch067 on May 17, 2017 1:09:37 GMT -5
The specific gravity that I come up with is roughly 2.25 (dry weight=9g; wet weight=5g). ...Doesn't help much - does it?
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Post by gmitch067 on May 27, 2017 7:36:39 GMT -5
You cut it. How hard/tough is it? Looks like it may be jade. And the polish is an orange peel effect from polish. Try diamond or tin oxide polish for jade. Is it very hard and tough? Talk about delayed action (or in my case delayed thinking...) You say that "orange peel" effect is a result of the polish - not the characteristic of the rock that can be used in its ID? The green rock in the photo was only polished using SiC wet/dry sanding (No modern cabbing equipment here... just 220-2000 grit papers on a kitchen counter cutting board - with a lot of elbow greese). Would this be a case of undercutting? (I have SiC papers that will go to 5000 grit, but the orange peel effect did not show until I was past 600 grit - getting worse with the higher grit.) How can I get rid of that? As for the rock's ID, with a low SG, I am leaning toward Bloodstone. In the photo you can see an orange deposit in a few places - not red... but...( )
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Deleted
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Post by Deleted on May 27, 2017 8:08:45 GMT -5
Definitely NOT bloodstone.
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Post by gmitch067 on May 27, 2017 22:24:01 GMT -5
Oh well...Another one to eliminate from the list... Thank you $hotgunner!
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Post by gmitch067 on May 28, 2017 16:51:47 GMT -5
Definitely NOT bloodstone. OK $hotgunner... 2 more... Maybe... Green Jasper - SG 2.5-2.6; 6.5-7 Mohs or Maw Sit Sit - SG 2.5-3.5; 6-7 Mohs (base substrate without any green stripes???) Or... it could just be jade - like you postulated at the beginning. LOL!
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Deleted
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Post by Deleted on May 28, 2017 17:14:30 GMT -5
I think your specific gravity is flawed. Your weights are to one significant digit so you cannot say 5-9 grams and 2.25 SG. All you get to say is 2 sg so without a better weight I'm sticking with jade or something in that category. You need 5.00 and 9.00 to say 2.25 SG Definitely not chert. Wikipedia on significant figures
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Post by gmitch067 on May 28, 2017 20:03:24 GMT -5
yes... You are probably right+++ My SG figuring is very primitive (but it WAS a fun side trip in rock ID!).
My scale was a kitchen food portion weigher used in dieting - only good to 1 significant figure when in the grams setting. It is a very cruel beastie to me (My one significant figure is "chunkie")! LOL!!!
Is the stone worth saving from its case of orange peel dermatitis? Was my "elbow grease" shine too vigorous? I guess I can re-sand it down to 600 grit and try again. Or I can plop it into my UV-10 at the 600 grit stage and go directly to a TO polish.
BTW... What type of lizard is your member pic of? At first I wanted to say that it is a Gila Monster - but the nose is neither the squished-in type I remember - nor is the tail blunt. Is that it's original tail (lizards grow back their tails if lost - usually in a light color)? Regardless... I still think it is cool!
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Deleted
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Post by Deleted on May 28, 2017 20:29:33 GMT -5
yes... You are probably right+++ My SG figuring is very primitive (but it WAS a fun side trip in rock ID!). My scale was a kitchen food portion weigher used in dieting - only good to 1 significant figure when in the grams setting. It is a very cruel beastie to me (My one significant figure is "chunkie")! LOL!!! Is the stone worth saving from its case of orange peel dermatitis? Was my "elbow grease" shine too vigorous? I guess I can re-sand it down to 600 grit and try again. Or I can plop it into my UV-10 at the 600 grit stage and go directly to a TO polish. BTW... What type of lizard is your member pic of? At first I wanted to say that it is a Gila Monster - but the nose is neither the squished-in type I remember - nor is the tail blunt. Is that it's original tail (lizards grow back their tails if lost - usually in a light color)? Regardless... I still think it is cool! Here is my chunkie reply! It's a chuckwalla. Sauromalus obesus. As for polishing your stone? No clue. Sorry. Lol I would try backing up a step or two, and use diamond I stead of other grits.
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