Hollowed-out (skeleton) galenas from Bulgaria showed up at the Denver and Munich gem shows a couple years ago and dazzled the mineral collecting world. They reportedly came from an old mine with little hope of additional specimens ever being found. Prices rose to $3,000 - $4,500 for the best specimens.
However, a few questions were raised among collectors about the origin of these unusual minerals and 12-year collector Jessica Simonoff [right] arranged access to an SEM at James Madison University.
[update and correction 2-17-11, 0900: I originally attributed Jessica's access to the SEM through her father, Bob Simonoff. However he straightened me out this morning with the comment posted below and repeated here: " Jessica did many experiments on these crystals (UV light to look for glue, acetone testing to determine if there was glue involved, hours of microscopic examination, etc.). When none of these tests were conclusive, she contacted Dr Lance Kearns of James Madison University, whom she had met earlier as a result of a local mineral club field trip. She explained what she had been doing and he agreed to work with her on the SEM to study the pieces. This is when they found the evidence on the 2 pieces and the 1 control piece they studied. Jessica and Dr. Kearns co-published the paper in Mineral News. Jessica’s father provided the requisite taxi services and any other help that was requested, but was not directly involved in authoring the paper." Thanks for the correction!]
There she discovered microabrasion marks and tiny spherules that were used to create the specimens she examined. Jessica and Dr. Kearns published a report in Mineral News and posted an article in Mindat.org, suggesting that many of the reverse-skeletal galenas on the market are man-made and thus fakes. Her expose is rocking the mineral collecting world.
Copies of her article were circulated on the floor of the just-completed Tucson Gem & Mineral Show. My contact says dealers who had any of the skeletal galenas in their booths pulled them immediately while they check on their authenticity.
update 2, 2-17-11: read more about Jessica's work at the Mineral Bliss blog and the recognition she received from the Friends of Mineralogy at last weeks Tucson Gem & Mineral Show.
Ref: Jessica Simonoff and Lance Kearns, Skeletal Galena Crystals from Madan, Bulgaria - Natural or Fake?, Mineral News, December, 2010
Ätna: kleine Lavafontäne
8 hours ago