Mineral: Galena
Locality: Gibraltar Mine, Cueva de las Espadas, Naica, Municipio Saucillo, Chihuahua, Mexico
Dimensions: 15 x 10 x 9.5 cm / main crystal: 4.8 cm.
Description: Mass: 2180 g
MIM number:1929
Group of very bright and well-formed galena crystals with black sphalerite crystals at the base. Usually the galena crystals adopt classical forms of the cubic crystal system. The crystals of this sample have flattened shapes with a hexagonal outline: These are called Gonderbach twins, and result from two adjacent crystals sharing the same face of an octahedron, but rotated 180° with respect to each other. It is rare to have in a sample as many well-formed, shiny and intact such twins.
Photographer: FMI / Benjamin DeCamp
Ex collections: Eugene Schlepp (USA), Marvin Rausch (USA), Bruce Oreck (USA)
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