Seymchan is an unusual pallasite (a rare type of meteorite which typically contains both metal and olivine crystals. The complete slice of Seymchan now offered, however, is of the pure metal variety. A prominent Widmanstätten pattern is in evidence; this latticework is indicative of a slow cooling rate that provided sufficient time — millions of years — for the two metallic alloys to form their intricate intergrowth. It is diagnostic in the identification of an iron meteorite. Seymchan meteorites are renowned for some of the most robust crystalline patterns seen, and this large complete slice is, with its shimmering etch, in the tradition of the best examples.