02/03/2025
In 2013, a special gold exhibit at the Munich Mineral Show featured some truly extraordinary gold specimens reported to be from the Lena Goldfields in Siberia. The Lena Goldfields are large placer deposits located in the Bodaibo region, approximately 150 km northeast of Lake Baikal along the eastern margin of the Siberian Craton. The Bodaibo region contains the largest placer gold reserves in the world. Prospectors first discovered gold in the area in the 1840s, and by 1860, it was recognized as a world-class deposit. The region is known for its remarkably large nuggets, such as the “Giant of Bodaibo,” found in 1957, which weighed 12.3 kg. Many of the large nuggets exhibit remnants or shapes of octahedral gold crystals.
The specimens on display in 2013 stunned the world — they were unlike anything found elsewhere. There are two distinct varieties: cubic specimens that display striations and resemble pyrite pseudomorphs, and hoppered octahedral crystals that are as large as 2.5 cm on each side. The specimens were (and remain) so exceptional that their display in Munich and subsequent mineral shows has generated considerable skepticism regarding their authenticity. They simply seem too good to be true.
That said, a dozen scholarly studies have failed to prove that they are man-made, and the body of evidence indicates that these are indeed mineralogical unicorns (some of which may be pressed unnaturally into matrix). At least one of the octahedrons has been confirmed as a single crystal (as determined by neutron scattering), with a U/Th helium date of approximately 430 million years. The cubic specimens are pseudomorphs after pyrite, and a January 2025 article in the “Journal of Crystals” presents a plausible mechanism for the replacement of pyrite through successive episodes of dissolution and precipitation of nanoparticles of gold.
Despite the substantial amount of analytical work supporting the authenticity of these remarkable specimens, skepticism persists. In some mineral forums, several participants claim that these unicorns are the work of a skilled craftsman in a secretive St. Petersburg workshop. However, there is no physical evidence that such a magical place exists. The finest examples do, however, appear to have been assembled as a single suite, the last of which are available in Marcus Budil’s booth in the Mineral Galleries on Lester.
— Terry C. Wallace Jr.