Morphological characteristics of diamonds from Efimovskoe deposit

The morphology and the micro-relief of diamonds from the first indigenous field «Efimovskoe» (Perm region) were studied. Along with a substantial degree of dissolution, specific etch pits and negative circular sculpture are identified, which is a typomorphic feature of diamonds from the Urals deposits. On the basis of analysis of the revealed morphological features the basic events in history of the Urals diamonds are reconstructed - formation of plane-faced forms in mantle conditions, mechanical deformations and volume dissolution at mantle diapirism, etching by fluid-saturated lamproite (?) melt at its boiling up during eruption.