- Siglo Veinte Mine (Siglo XX Mine; Llallagua Mine; Catavi), Llallagua, Rafael Bustillo Province, Potosi Department, Bolivia
- Toenail, 3.0 x 2.4 x 1.5 cm
Vauxite is known in many forms and colors from Siglo XX, and this piece shows some of the darkest blue Vauxite that one will see, especially in smaller crystals. The piece hosts radiating crystal groups of deep blue color Vauxite blades which are wedged between a thin plate of white botryoidal Wavellite matrix. It is very difficult to obtain Vauxite crystals on matrix from this locality, and as you can see, the Vauxite aggregates are simply gorgeous under magnification. The color is about as deep as it gets for the species. Ex. Brian Kosnar.