Author Topic: carving gemstones dry  (Read 11020 times)

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3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #45 on: February 03, 2012, 08:25:50 AM »
Last best info I had says that the "yellow" fibers are indeed replaced (no longer asbestos) but that the blue fibers (Hawks Eye, or Hawk Eye) are not replaced and are still asbestos.

No quite.  If the asbestos fibers are replaced by silica before their alteration to iron oxides takes place, a rarer blue form of Tiger's eye known as Hawk's eye results.  The color of tiger eye is the result of impurities, not incomplete replacement.  I actually took a piece to work and did an atomic absorption test just to be sure.  That's why it took so long to reply.

Not that I doubt you did but the debate on this is old -- and my health ain't so good -- I'd rather not take even a remote chance:

Tiger's eye - Wikipedia

specifically, "A member of the quartz group, it is a classic example of pseudomorphous replacement by silica of fibrous crocidolite (blue asbestos).  An incompletely silicified blue variant is called Hawk's eye."

I have read both that the blue is simply pigment discoloring the quartz that has completely replaced the asbestos and that it is actually still asbestos.

Did you use a gas spectrometer?
-frank-

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slabbercabber

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Re: carving gemstones dry
« Reply #46 on: February 03, 2012, 04:05:50 PM »
We call it an atomic absorption but yes I am pretty sure it is a gas chromatagraph.  I should admit I do not have the ability to use it myself.  The lab techs are very protective of their baby.  The telltale in this case is that there is no trace of sodium.  That pretty much rules out any chance of crocidolite as I see the definition.  If I am missing something, let me know.  I'll bug the techs again.

3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #47 on: February 04, 2012, 01:37:45 AM »
We call it an atomic absorption but yes I am pretty sure it is a gas chromatagraph.  I should admit I do not have the ability to use it myself.  The lab techs are very protective of their baby.  The telltale in this case is that there is no trace of sodium.  That pretty much rules out any chance of crocidolite as I see the definition.  If I am missing something, let me know.  I'll bug the techs again.

With the lab, probably not - sounds like you know chemistry far better than I do and you're probably right. Still can't get the jitter out of the bug here though for whatever reason. Maybe if several specimens from different locations and of different colors were spec'd I'd feel dumb enough to force myself over my fear of it  dunno28

Kind of like malachite - I hear more good stories than bad about it yet the bad ones are scary, so I stay away from it (for now anyway - doesn't scare near as much as unlikely asbestos)
-frank-

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Pat

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Re: carving gemstones dry
« Reply #48 on: March 12, 2012, 11:16:05 AM »
I'm quite to new carving and cabbing, but like them both very much.  I normally wear safety glasses and a paper nose/mouth mask.  In both cases, I use water, but in carving there is a little bit of dry with the silicon carbide wheels toward the end.

I'd like some suggestions for a good all-purpose mask, something that isn't intrusive to vision, but effective. 

3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #49 on: March 12, 2012, 05:48:21 PM »
I'm quite to new carving and cabbing, but like them both very much.  I normally wear safety glasses and a paper nose/mouth mask.  In both cases, I use water, but in carving there is a little bit of dry with the silicon carbide wheels toward the end.

I'd like some suggestions for a good all-purpose mask, something that isn't intrusive to vision, but effective. 
I use a 3M half face mask with 3M 60921 cartridges. Technically the 2091 filters should work I believe, but I seem to be spared ill effects only with the 60921 filters. Read this thread from the start for the debate/discussion on this and other fine things.
-frank-

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jackd

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Re: carving gemstones dry
« Reply #50 on: May 14, 2012, 11:56:36 AM »
What types are most carvers using?

3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #51 on: May 14, 2012, 12:16:19 PM »
What types are most carvers using?

I've a feeling most are using just the paper face masks.
-frank-

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Apehanger

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Re: carving gemstones dry
« Reply #52 on: May 14, 2012, 01:03:45 PM »
I have a 3M respirator

http://www.screwfix.com/p/3m-maintenance-free-respirator/13038

I get it through work, so it doesn't cost me  dancer27

ScarlettoSara

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Re: carving gemstones dry
« Reply #53 on: May 14, 2012, 03:13:35 PM »
Thats a good Respirator Roy:)
When I first started polishing rocks my eyes swelled up and itched big time.
I think it was the Aluminum Oxide.

jackd

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Re: carving gemstones dry
« Reply #54 on: May 14, 2012, 07:32:09 PM »
Apehanger, thanks for the link it sure has some good reviews....

...jack

3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #55 on: June 08, 2012, 10:00:51 AM »
I started cutting some rhyolite the other day - forgot my mask - two days quite ill == stupid. So last night I start again, going at it with sic stone wheels. Proudly (ha...) wearing mask, when something hits me in the eye.

I think both are crucial if you're not a risk taker. If you are a risk taker then go base jumping. Better to die the scenic way than looking at rock mud...
-frank-

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ScarlettoSara

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Re: carving gemstones dry
« Reply #56 on: June 08, 2012, 10:05:08 AM »
Hell yes go as fast as you can to the cliff and jump off screaming....... YEEEEEEEEEEEEEEEEEEEEEEHAWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW
http://www.youtube.com/watch?v=Z6xsKsJqVyg

3rdRockFromTheFun

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Re: carving gemstones dry
« Reply #57 on: June 08, 2012, 11:24:36 AM »
Don't forget the airbags!
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Barclay

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Re: carving gemstones dry
« Reply #58 on: September 20, 2013, 06:23:35 PM »
Being in the environmental/safety business I read this thread with some interest even though it is old.  One issue I did not hear discussed was purity.  Mother Nature usually does not grace us with chemically pure rocks, hence the refining industry.  Arsenic and copper usually occur together.  How much arsenic is in that piece of malachite, azurite or turquoise varies piece to piece or even within the same piece.  The problem is that arsenic is toxic in really small amounts.  The same issue with tiger eye.  They yellow stuff is altered blue asbestos, but how many of us have x-ray vision to see if the entire stone is altered?  Those microscopic asbestos fibers are really hard to see.  Water is not the total solution.  How many of us have clean lapidary equipment?   That asbestos or arsenic or other nasty element may have come off the stone in a drop of water, but saw blades and grinding wheels fling them everywhere.  Then they sit on the ground and turn into dry particles again waiting for us to sweep up or walk through them.  There used to be a chrome plater in San Diego called Master Platers.  You can Google them for the whole story.  In a nutshell they set up a monitoring station next door and the highest off site emissions were on a Saturday when the shop was closed and someone was just sweeping the floor.  Dust masks are only good for nuisance dust, if you want protection from small particles you need a respirator with a HEPA cartridge.  Some things to consider.
Lowly Padawan of rocks