FIBROLITE
FIBROLITE See “Sillimanite”.
FROODITE
FROODITE Froodite – α-PdBi2 – is a very rare sulfide (an alloy of metalloids with Platinum Group Elements), of no importance as an ore. It may contain Te. 1. Characteristics Crystal system: Monoclinic prismatic. Color: Gray. Highly reflective in silvery white. Tarnishes quickly. Habit: Rounded grains. Cleavage: {100} perfect, {001} distinct. Tenacity: Brittle Twinning: Sometimes. […]
FORSTERITE
FORSTERITE Introduction See “Olivine”
FAYALITE
FAYALITE See “Olivine”.
FAHLORE
FAHLORE See “Tetrahedrite-Tennantite” “Fahlore” is derived from the German “Fahlerz” (“pale ore”, an ore with “faded” colors) and the English suffix “-ore”. “Fahlore” is used since 1805.
FERBERITE
FERBERITE See “Wolframite”
FÜLÖPPITE
FÜLÖPPITE Fülöppite – Pb3Sb8S15 – is an extremely rare sulfosalt that is part of polymetallic hydrothermal ores of the Ag-Pb-Sb-Zn paragenesis. It is classified in the Plagionite Group, being very similar to plagionite. 1. Characteristics Crystal system: Monoclinic prismatic. Color: Lead gray. Habit: Pyramidal, short prismatic, fibrous. May be thick tabular. Curved crystals are frequent. […]
FLUORITE
FLUORITE Fluorite – CaF2 – is a very common halide, a strategic ore, essential in steel making and metallurgy as a flux, also in the chemical industry (HF manufacturing) and for many other applications. The main source of “metallurgical grade fluorite” are sulphide ores of lead and zinc with fluorite gangue. In addition, due to […]