Gratonite - rare find circa 1900

Item Description

This item is part of a special benefit auction for the Rice Museum of Rocks & Minerals (ricenorthwestmuseum.org). Items are either deaccessions from the museum's collection or were donated by generous supporters listed below.

Auction open April 1, 2021 through April 17, 2021.

Billing for this auction will occur on Monday, April 19, for payment using PayPal or credit card. Shipping will be billed at cost, or please contact brandy@mineralauctions.com if you'd like to plan on picking up items at future shows or during a stop through Dallas.

Gratonite is a lead arsenic sulfosalt and Cerro de Pasco is the type locality, long since extinct for specimens. Aside from the significance of the locality, this location ALSO produced the best of species in sharp clusters such as this. This is an exceptional thumbnail cluster for the species consisting of 1 to 4 mm, very well-formed, bright, metallic gray, complex, almost equant crystals that are nicely isolated in the cluster and very distinct. The luster on these is excellent. Although Gratonite crystallizes in the hexagonal-rhombohedral system, these exceptional crystals look almost like dodecahedrons. This piece is of exceptional quality with large crystals for the species and it has great composition. It's a competition level thumbnail aside from only a few incomplete crystals. This specimen probably originated from finds in the 1890s through the first decades of the 20th Century at Cerro de Pasco. They are all old specimens! A suggested valuation on this is $1500