Chinese fluorite

Has anyone seen these "new" chinese fluorites yet? Seem to be quite new on the market, sure to appear in Munich and Tucson.

While the dealers swear to high heaven those to have grown naturally (some may have realized something's with their purchase, now trying to pass the hot potato), with localities given as Henan or Yunnan Province (or any other random place), a reliable source told me the pieces are actually carved from massive fluorite (said from Inner Mongolia), then treated with hydrofluoric acid to mask the carving marks, finally oiled of course. Note the rough, etched surface. Also, fluorite balls forming along pentagondodecs seems rather unlikely, what do you think?

Hydrofluoric wouldn't affect fluorite. Possibly another strong mineral acid such as HCl?

But yes, they scream FAKE at you.

Fluorite is also unaffected by HCl.

Fluorite IS affected by HCl, even when relatively dilute, it can etch crystal surfaces, which is why it's never a good idea to use HCl to clean Fluorite. I've no idea whether concentrated HCl can etch it more significantly or not.

Jolyon

??? I have cleaned fluorite with HCL, even etched it out of calcite without affecting it. I just checked Jesse Crawford's list and he agrees with you, so I'm sure you're right, but that has been my experience. Could there be a difference in solubility between localities or crystal forms?

It all depends on the concentration of acid and the amount of time you have it in there.

I generally use phosphoric acid or organic acids to clean Fluorite now.

Jolyon

H₂SO₄ + CaF₂ ==> CaSO₄ + 2 HF ?



Edited 1 time(s). Last edit at 10/27/2009 10:05PM by Philippe M. Belley.

I saw some fantastic artificially grown fluorite on matrix specimens in the mineral museum in the Geological Institute in the Novosibirsk Academic City some time ago. The museum displayed a variety of habits and colors, all acknowledged to be man made. While these Chinese examples may or may not be natural, growing fluorite in the lab is apparently quite possible.

Jeffery,
Are you sure these were fluorite? I think there was mention of these in a former forum thread and it turned out that they were not fluorites.

Rock Currier
Crystals not pistols.

Rock - I visited this museum after a 36+ hour trip, which including an "invigorating" 12 hour lay-over at the domestic air terminal in Moscow, eventually arriving in Novosibirsk at about 5:00 AM, local time. I was then given a whirl-wind tour of the Academic City, including a visit to the mineral museum - so all things considered, I could be mistaken, but I am 95% certain there were fluorite, amongst other man made minerals.

The prior thread is "lab grown specimens" [www.mindat.org], Pavel seems to think that what I saw was tschermigite of a violet hue, but I clearly remember seeing a range of pastel colors and labels indicating these were fluorite. I could be mistaken.

The museum was also notable for having a log, 1 meter diameter, 4 meters long, of typical charoite gemmy material.

The charoite specimen is quite believable. I have seen some almost as big waiting to be cut up into smaller pieces and have seen pictures of the deposit that make me think that specimens ten times that size might be possible if it were possible to move them.

Rock Currier
Crystals not pistols.

You don't even need any acid to etch fluorite - Running water will do it, if you have a modest amount of patience.

How much is a modest amount?

Rock Currier
Crystals not pistols.

Just a few weeks - I know that's asking a lot in this age of instant gratification. ;-))