Sodabowski
Thomas Rodriguez
Enjoy the Walbanking time Brumble-gum!
Black Spinel - cutting options and are large ones rare?
- Thread starter Twapster
- Start date
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Twapster
Peter
Brumble-Gum said:
Will do BG
excalibur63
Gordon
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Where I prospect there are rocks that look like black jack whilst in the water, I keep them. But when I get home I spread all my finds out on the sorting table to completely dry. It's only then that I can visually spot the difference, as the look alikes usually show up minute "pitting" on the surface, and Black Jack appears smooth.
excalibur63
Gordon
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That's right Lefty, Black Jack does have that chalkboard finish when dry, but in the creeks all wet, damp & usually overcast (Tasmania lol! ) it is difficult to distinguish between some of the look alike stones.
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Hi all, (apologies for jumping into your thread twapster). I am new to the gemstone side of prospecting, but my sons & I have always had a thing for bringing home peculiar rocks when poking about in streams etc.... Anyhow I stumbled across this thread when researching my latest find & viola.... From what I can see you guys/girls are in recent conversation about this mineral.... I quickly threw my three blacks on the scales & came up with 399.15cts total. The biggest rock being 299 odd cts!! I am in dire need of confirmation as I too would like to retire early to find more peculiar rocks!! ???? I have taken some pics but I am unsure on how to put them up here! ? Any help would be greatly appreciated.
Sodabowski
Thomas Rodriguez
Hi Gippy, welcome aboard. Click on that funny looking icon right above the text area , between the Acrobat logo and the text bubble logo (lil blue frame thing). It will pop up a new window, in which you have a button to select a file from your computer. Then click the "insert image/s" and voila (not "viola", it means "raped" at the past tense, as in sexual abuse).
Twapster
Peter
Gippyspecker said:
Bring it on mate, as long as you tell us where the secret spot is!!!
To be honest I cant even recall where I picked up some of my rocks....I have a habit of just seeing something I like and putting it in my pocket or chucking it in the drivers consol. I look at it when I get home or find a random rock in my car. Where did that one come from?
I certainly haven't found many big spinel so would love top see some pics!!!!
Hey Twapster, I just remembered, do a streak test with it on the back of a ceramic tile, Spinel will leave no streak, where as other Black rocks will generally leave a Black streak.
G
Guest
Is that on the clay side or the glazed side? Clay side I presume.
Sodabowski
Thomas Rodriguez
Am I the only one to think "cameo" when it comes to dark opaque stones like black jack?
Retirement Stone said:
Yes on the clay side mate, nearly forgot about the good ol streak test. Saw a Black rock I'd been meaning to do this morning, had a Black streak doh.
Do a read up on it, pretty good for helping to ID quite a few different rocks and minerals.
G
Guest
Sodabowski said:
YES
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Sodabowski said:
The trouble for Cameo is that black spinel lacks contrast, it is all black... not sure it is the best.
I am faceting a black jack with a "Double French Star" diagram, just to see how it will polish and the reflections.
I should finish tonight or Sunday, depending of the weather (better to the beach or fishing than staying home
). I'll post the results here.
Sodabowski
Thomas Rodriguez
Well I'm thinking "doublet" when saying "cameo+black spinel", as a backing for, say, lesser quality opal. Might give it a shot since I have both Hey can't wait to see your faceting results!
Hey can't wait to see your faceting results!
Twapster
Peter
Heatho said:
Champion, thats what I needed! Now just need to find a ceramic tile lol
Streak plates have a hardness of about 6.5, so if you want to test the streak of anything harder, get out the hammer! Maybe not gonna work.
Twapster said:
Yeah and if it leaves no streak you will be looking good for Spinel. If it leaves a streak it's not Spinel. That rock almost certainly won't be over 7 hardness if it's not Spinel either mate.
Twapster
Peter
Left a white streak. ie scratch on the bottom of a bath tile?
Spinel should leave a white or no steak, so looking good, it's not a definitive test though. SG test next.
