Spinele skał metamorficznych z Horczak i Krynek

Abstract

SPINELS IN METAMORPHIC ROCKS FROM HORCZAKI AND KRYNKI

The paper deals with the Study on rocks containing spinels. In two bore holes at Horczaki magnetite was found to occur in two types of rocks: 1) in laminated amphibole-magnetite-quartz rocks with garnets, apatite and biotite, and 2) in distinctly laminated quartz-magnetite-amphibole-epidote schists with biotite, garnets and apatite. The laminae differ in their mineral compositions and in proportions of minerals they contain. In these rocks magnetite occurs in three generations corresponding to the successive stages of rock metamorphism.

The magnetite of first generation forms, in two rock types, xenomorphic often elongated groups of crystals intergrowth with the original minerals of the rock. In relation to these minerals it is of the same age and of equal rank.