Grey inclusions of the extremely rare tantalum mineral alumotantite from the type locality in Russia.

Alumotantite occurs as grey inclusions in the one-side polished specimen, mainly inside the circle (see photo 5 and others) but also in others parts of the specimen alumotantite can be found (for example photo 8)

Analyzed specimen by SEM/EDS  see copy enclosed.

After Mindat we know that : 

"This is a rare mineral. Perhaps no more than two small specimens. The mineral is not recognizable by eye. Anatoliy Voloshin collected the type material and co-authored the description. A few probe mounts (10?) were made and analyzed with an EDS (energy dispersive spectrometer). Each probe mount contained perhaps four rock fragments less than 5 mm each in which the mineral was identified. Fragments (quarter sections) of these probe mounts found their way to the rare specimen market and were purchased by a few collectors and museums.1 The type material is located in the Geology Museum of the Academy of Sciences, Apatity, Russia"

This specimen at auction is probably one of these probe mounts (10?), so a real rarity !..

Ex Vandenbroucke Museum collection from Waregem, Belgium.

No duplicates available !