Canyon Diablo Graphite Nodules
Find / Fall: Find 1891
Location: Arizona, USA
Classification: Iron, IAB-MG
Total Known Weight: 30 t
Canyon Diablo Graphite Nodules are fascinating objects with a long history of study by scientists which even continues today. Graphite nodules are found in other iron meteorites but Canyon Diablo has produced the largest and the most numerous. Graphite is found as irregular masses associated with other minerals such as troilite and scriebersite in Canyon Diablo meteorites. However, the large more or less spherical masses of graphite have a different composition. Canyon Diablo Graphite Nodules are often crisscrossed by veins of metal or may contain only spots of metal. Theories regarding how and when the veins formed are numerous but recent work would suggest that the veins formed early in the solar system by impact induced shock melting. Results from Re, Os chronometry favor vein formation in the nodules during a period of impacts before 4Ga. This is a date for impacts seen in many types of meteorites.
The veins themselves are mostly characterized by depleted amounts of Re, Os, Ir, and Pt compared to the metal of the meteorite itself. This has strongly suggested to some scientists that the metal of the veins was injected into the graphite during heating in impact events. Though the recent impact with Earth during the formation of the Barringer Crater (Meteor Crater) has not been ruled out. Evidence today would suggest that there may have been multiple impacts in space before the asteroid arrived to Earth.
Graphite nodules are on the whole rather soft and easily shined up during preparation but some contain numerous small diamonds that can on occasion make cutting the nodules very difficult.
Canyon Diablo Graphite Nodules make an excellent addition to any collection of Meteor Crater materials or any collection of meteorites for that matter. They are highly prized by collectors and only seen on the meteorite market sporadically.
Canyon Diablo Meteorite Information
