Cabinet, 10.1 x 7.8 x 4.6 cm
Luc Yen, Yenbai (Yen Bai) Province, Vietnam

This is a rare example of a spinel twinned spinel crystal NEXT TO an untwinned crystal in close proximity. Such pieces are few! The large spinel twin here is 3-dimensional, fairly gemmy, and textbook-sharp in form. It is over 2 cm at longest width, at its base. The distorted, elongated octohedron next to it is just about 2 cm. This piece was expertly worked to excavate the crystals and leave them isolated on contrasting marble matrix - but you can see as how a misstep during prep would have destroyed this unusual specimen.