A Kyanite crystal in typical Kyanite-Garnet-Biotite Gneiss. This type of rock occurs in bands in the Belomorian Domain.
This means similar samples can be found in western Kola and Northern Karelia. This sample is believed to be from Rikolatva.
A different appearance is this sample. Here Kyanite sits in Kyanite-(Staurolite) schist. This is common in the Keivy Domain, where there are
about 27 economical Kyanite deposits.
Some rocks present a lot of information, just by looking at them. This is such an example. It is a Kyanite pseudomorph after Chiastolite (Andalusite) from Semyatrovye in the Keivy mountains, Kola. Chiastolite is a variety of Andalusite in which graphite forms a cross shaped intrusion in Andalusite. The mineral is formed in terrestrial Archean gneiss. This kind of rock is rich in graphite, so the Chiastolite variety makes sense. Andalusite is stable at normal pressures. At one time the pressure in the rock increased the Andalusite recrystallized into Kyanite.
A blue Kyanite grain in eklogite like rock from the Marun Keu complex, Polar Ural
A classic Kyanite locality is Borisovkyi Sopki in the southern Ural.
In Chainyt, southern Yakutia, Kyanite occurs with Ruby. This rock is locally used for ornamental purposes.
[all photo/collection: Maurice de Graaf]