THE MINERAL FEDORITE

Chemistry: (NA, K)_2-3(Ca, Na)₇(Si₄O₈)(Si₄O₁₀)₃(F, Cl, OH)₂ - 3.5H₂O, Hydrated Sodium Potassium Calcium Silicate Fluoride Chloride Hydroxide.
Class: Silicates
Subclass: Phyllosilicates
Uses: Only as mineral specimens.
Specimens

Fedorite is a rare alkali mineral from the famous Kola Peninsula, of Russia. It is named for one of the founders of modern crystallography, Russian scientist Evgraf Stepanovich Fedorov. It forms nice "mica" like crystals that can have an attractive light red color. Fedorite crystals can be found in veins cutting through sandstone beds associated with minerals such as apophyllite and narsarsukite.

PHYSICAL CHARACTERISTICS:

Color is white, colorless and light raspberry-red.
Luster is vitreous to pearly.
Transparency: Crystals are transparent.
Crystal System is triclinic; bar 1
Crystal Habits include pseudohexagonal tabular crystals similar to mica books.
Cleavage is perfect in one direction (basal).
Specific Gravity is approximately 2.4 to 2.6 (average)
Streak is white.
Associated Minerals are apophyllite, narsarsukite and quartz.
Notable Occurrences include the type locality of Turyiy Peninsula, Kola Peninsula and Murun massif, Russia.
Best Field Indicators are crystal habit, color, luster, associations and locality.