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Au4Gold2

Quartz / Gold & Hydrofluoric Acid

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Looking for any information on who provides lab services to clean mineral specimens in California. I am sure I am can't be the only one interested in such a service. i won't mess with this wicked and nasty chemical, but some Quartz with gold specimens would look a lot better with an acid treatment.

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There are not that many people who do this as getting the full beauty out of a gold specimen really is an art and HF is dangerous stuff. I would recommend contacting Dave Variboff of gold bay. Dave does a lot of that type of work. 

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some Quartz with gold specimens would look a lot better with an acid treatment.

Some is definitely the keyword, and I'd say the vast majority will not improve much with HF treatment and actually look better as-is or with a less harsh treatment. Those big crystalline specimens you see at the major gem shows are HF treated, but it exposes those nice gold crystals, where as the average specimen will often turn out crumbly or porous instead. But it all depends on the piece of course.

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Thanks Chris, I have had this piece a few years and have to admit its like having a gift in a box....you just want to open it up o see the prize. The specimen weighs 8 ounces and shows real nice gold, did a continuity test on it and its all connected. Conservatively speaking I am thinking 2-3 ounces of pretty in the joke of the rock. May get it X-Rayed to take a look inside before I do the treatment..I know the Collectors Edge has a 2500 square foot lab and specializes in these sorts of things, but its in Colorado...would be a good opportunity for someone in California...  :) 

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I am in Northern California and had a similar specimen hf treated. It was on the cover of ICMJ several years ago (along with an article).

I took it to a guy that owns a chemical store and he put the specimen in a clear container with hf and I took it home. He put the container inside another container to make it safer to transport and store. Although he said he would keep it at his shop and I could stop in anytime to check on it, it just seemed safer staying with me (it had just under 4 ounces of gold in it). I kept it in a really safe place (away from pets, kids, and wife) at home and even though the container was leak proof, I wore rubber chemical gloves every time I touched the container. It took  couple weeks to eat all the quartz. When the quartz was all gone, I took it back to the guy and he poured off the acid and neutralized the gold with another solution. I offered him a few nuggets in return and he would not accept anything. He said he enjoyed seeing the rock turn into something nice.

008.JPG

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So, Matt, what does the finished product look like?

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Matt thats a beauty !! I can understand keeping it at home......would hate to lose a piece like that. If anything happened to it under your own watch...you can blame yourself  lol...and this way you stay friends...

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Ace Hdwr sells a product that has a weak solution of hydrofluoric acid called wink. Buy the one that is for cleaning concrete. It not only cleans quartz, but it will desolve the quartz in time. 

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This is what it looks like after the hf treatment. Sorry LipCa, I couldn't find the after pictures this morning.

010.JPG

Specimen 2.jpg

003.JPG

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