SYNTAXY OF TITANITE, AEGIRINE AND ECKERMANNITE IN ALKALI SYENITE PEGMATITES OF THE VISHNEVYE MOUNTAINS (SOUTH URALS)

Abstract

Crystallographic orientation of titanite intergrowths with aegirine and eckermannite was found in alkali syenite pegmatites of the Vishnevye Mountains: the titanite face ( 1 11) is parallel to pyroxene and amphibole face (010) and the titanite face (110) is parallel to pyroxene face (110). Aegirine is a host mineral for oriented intergrowths of titanite and eckermannite and chaotic inclusions of feldspar, apatite-(F), monazite-(Ce), hydroxycalciopyrochlore, lantanite-(Ce), zircon, rutile, pyrite, galena and barite. Pyrite is characterized by oriented intergrowths which calcite crystals: the axis L3 of pyrite and calcite is parallel and pyrite face (100) is parallel to calcite face (10 1 1). Eckermannite, hydroxycalciopyrochlore and lantanite-(Ce) were found for the first time in pegmatites of the Vishnevye Mountains.

Keywords

• oriented intergrowths of minerals
• titanite
• aegirine
• eckermannite
• hydroxycalciopyrochlore
• lantanite-(ce)
• alkali syenite pegmatites
• vishnevye mountains
• urals