The main mass of 272.3 kilograms (600 lb) was found during a survey in June 1967 by geologist F. A. Mednikov.

Remarkably, about 20% of the new specimens were found to contain olivine crystals,[2] and so revealed the silicated nature of the meteorite.

The pallasitic structure was not previously discovered during studies on small metal-only sections of the original mass.

[3] Seymchan belongs to Main Group pallasites, but it is considered anomalous due to its high iridium content.

It is worthy to note that the specimen pictured to the left shows an interesting, seldom seen feature of iron meteorites.