Malachite, Star & Heart

[michael B]

Just thought I would post a pic of some malachite I double cabbed, I have never worked with this material before, chatoyant material from Congo Africa, I found it easy to polish compared to my nephrite jade, these cabs will be in the NSW lapidary councils gem show in October, the star was a challenge to keep the shape right.

 

Cheers Michael B

[Debbie K]

Michael:

 

I like the way you oriented the lines on both of these pieces; the straighter lines make the star look like it's a shooting star, and the curved ones in the heart echo the overall shape. Well done.

 

I love the color and design of malachite, just hate the extra steps to stay safe carving it, so I don't carve it much.

 

Hope you do well in your competition.

 

Debbie K

[michael B]

Thanks Debbie, this was the first time I have cabbed this material, very toxic and messy, I think I will stay with jade and rhodonite now, I done these just for the state show, it was very easy to polish, linde A on leather, normal cabbing is boring for me.

 

Cheers Michael B

[Janel]

What kind of 'toxic' is this material?

 

Janel

[michael B]

Janel

Cutting, grinding and polishing malachite can cause copper sulphate poisoning, can be absorbed through the lungs, skin, should always be worked wet, and all carving and polishing equipment should be cleaned after use, I have also been told a mask and gloves should be worn even when worked wet, prolonged use of this material is not a good idea, some Chinese carvers will no longer carve this material in large amounts.

 

michael B

[Janel]

Thank you Michael.

 

Janel

[DanM]

Janel

Cutting, grinding and polishing malachite can cause copper sulphate poisoning, can be absorbed through the lungs, skin, should always be worked wet, and all carving and polishing equipment should be cleaned after use, I have also been told a mask and gloves should be worn even when worked wet, prolonged use of this material is not a good idea, some Chinese carvers will no longer carve this material in large amounts.

 

michael B

 

I believe you have your chemicals mixed up.Malachite is Copper Carbonate Hydroxide and not copper sulfate.Actual malachite poisoning is rare.

[Debbie K]

Dan:

 

I researched this once before, and today did it again. Attached is a link to a MSDS for copper carbonate. My link I hope this link works.

 

From my understanding, most folks (except those with Wilson's disease) are able to eliminate copper quickly enough that it doesn't do too much damage. The problem seems to be with chronic or large exposures, which can damage organs (particularly kidneys and liver) before the body can get rid of it. The thing that concerns me, as a carver, is the mud that gets thrown everywhere which then turns to a fine powder which floats in the air when you try to clean it up. Whenever I have carved it, I wear a mask before and after and wash everything down at least twice to get rid of the dust.

 

I know that there is little documentation on the internet for the toxicity of working with malachite. But I defer to all the old-timer lapidarists who have come before me that tell me this stone is one of the most dangerous to work with, just as I listen to the woodcarvers about working with particular woods. It's probably true that I'm much more likely to have problems with the quartz due to silicosis, but I figure, why borrow trouble.

 

Debbie K