- Siglo Veinte Mine (Siglo XX Mine; Llallagua Mine; Catavi), Llallagua, Rafael Bustillo Province, Potosi Department, Bolivia
- Miniature, 5.0 x 3.6 x 2.0 cm
A classic and fine Wurtzite specimen from one of the most classic Bolivian localities extant. The piece consists of lustrous, metallic brown, very well-crystallized, textbook hexagonal "rosettes" of Wurtzite measuring up to 6 mm on matrix. This piece comes from the collection of the well known and now deceased Colorado geologist Allen Heyl (Aheylite) and was apparently in Martin Zinn's collection at one point according to the accompanying label.