Hollow galena crystals from Bulgaria

Saturday, January 8th, 2011

These first showed up at the Denver mineral show in 2009.
Galena in question, supposed natural specimen
Many people were suspicious about these being made by microabrasion, but nothing had been proven either way. I saw Ed Rosenzweig at the Houston mineral show and talked to him about the pieces. He was one of the main dealers selling them at the Springfield show, but as soon as controversy came up, he stopped selling them. He lent me five pieces of hollow galena that he had been told were natural. I also received two samples of hollow galena from an anonymous donor, which he had made by microabrasion, using a machine like the MicronBlaster MB10 Micro Sandblasting Unit.
Man-Made Hollow Galena made for testing
Lance Kearns at James Madison University offered to let me use the SEM there, so I chose two specimens from Ed and one fake to look at. The fake one still had remnants of abrasive material embedded in the surface – and so did the other two. Here is a picture of a glass ball in one of the specimens from Ed:
sphere of glass bead, introduced from micro-abrasion on the specimen
The other piece had crystals of aluminum silicate rather than glass spheres – but still abrasives!
aluminum silicate, a common material used for micro-abrasion, stuck in the surface of a galena crystal

This doesn’t prove that all of the hollow galenas are fakes, but there are definitely fake ones out there.

Jessica Simonoff, author of this post, is the youngest summer program intern in the geology division of The Smithsonian. This link is for the CLASSIC Smithsonian Handbook of Rocks and Minerals inspiring thousands of children around North America.