Abstract
Crystals KCl as undergone pressure induced polymorphic transformation were investigated. Microstmcture and crystallographic orientations of the crystals were studied at once after the pressure removal and as stayed at room temperature for some time. The occurrence of at least six systems of plane defects connected with high pressure treatment at 20 kMPa is found. Their crystallographic indices are determined. It is found that in KCl crystals after pressure induced polymorphic transformation recrystallization takes place at room temperature. Two stages of recrystallization at room temperature were observed: growth of twins of cubic texture and grain boundary migration.