Rockin the Rockies

Rockin the Rockies
Stowe Mtn

Saturday, September 7, 2013

More Fluorite at Lake George and Mineral Cleaning


View of the Tarryalls from my dig site
Whenever I hit a pocket of even common microcline I take home a few specimens for cleaning. I dug into an area that had all the right signs, but no amazonite or smokys. There were plates of well defined microcline, so I took a few of these nicer plates home for cleaning. I mentioned to my digging buddy Bob that there appeared to be a fluorite crystal on one of the plates. The plates were covered in orangish red pocket mud, so I soaked the crystals overnight and took a toothbrush to scrub them up a bit. Voila, not only was there one fluorite, but the plates were peppered with small deep purple fluorites. Now I get to go back to that site and remove all the plates for cleaning and redig the area more carefully to make sure I haven't missed anything. I should have a flat or two of nice fluorite on microcline with smokys. Small specimens but unique!

Pocket opening up

Bob taking a crack at the pocket, note old dig in rocks, somebody just missed this pocket

Gemmy fluorite on matrix with microcline and smoky quartz, Ray B said the darkness of fluorite may be associated with Columbite anybody know a reference on that, couldn't find anything via Google or Mindat
A quick word on cleaning: Some minerals are professionally cleaned. If you wish to pay more for the crystal than what it is worth have it professionally cleaned. I would only reserve the finest/rarest crystals for professional cleaning. DIY. Different minerals require different processes. I use a multistep process that can be found in different books authored by Sinkankas and Pearl ...  Step 1: Soak specimen in water and lightly scrub it. Step2: Resoak specimen with soap and warm water and rescrub. Step 3: Determine what mineral you have to apply the appropriate cleaning agent you might have a plate of different minerals (don't clean calcite with a strong acid or you won't have anything left). Step 4: Carefully clean your specimen with the appropriate cleaning agent on low heat and check it frequently. Make sure specimen is completely immersed in cleaning agent during the cleaning process.  Step 5: I sometimes clean things a second time in different acids depending on the stubbornness of the staining or impurities I want to get off the crystal. If you use acids be very careful. See cautions on labels and internet. If you have children, lock up the acids like you would a loaded gun. Step 6: If I'm satisfied with the cleaning process it is now time to neutralize any acid if used. The temperature of the neutralizing solution (baking soda) must be as warm if not warmer than any acid used. It is also recommended to leave the specimen in the neutralizing soln as long as it was in the acid bath, the base solution should be changed frequently. Finally you may need to either bead blast or use a water gun to get off residue. You may also use a water gun after step 2 as well. Finally rinse in soapy warm water and hopefully they look like something you want to keep.

For the fluorite on matrix I found, I used phosphoric acid at 20- 25% concentrate in step 3 at low heat for about 36 hours. I will add a few more pictures of the cleaned crystals next week.

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