Canyon Diablo is a nickel-iron meteorite, classified by the width of its widmanstatten pattern as a coarse octahedrite. The original huge mass fell approximately 30,000 years ago in Arizona USA, about 3 miles east of the Canyon. This meteorite has been known and collected since the mid 1800s and was known and used by Native Americans. From the late 19th to the mid 20th century the crater was the centre of a long dispute over its origin. Despite the fact that the site shows no evidence of volcanism, many geologists assumed it was an extinct volcano. The debate was settled in the 1950’s following cometary Astronomer Eugene Shoemaker’s study of the crater. The specimen has been treated with light gun oil to make it stable. It should require minimum maintenance.