LABRADORITE
LABRADORITE See “PLAGIOCLASE”
LUZONITE
LUZONITE Luzonite – Cu3AsS4 – is a rarer sulfide, occurring as a primary mineral in copper ores. It is part of the Stannite Group and contains 48.4% Cu. As impurity, may contain Sb. 1. Characteristics Crystal system: Tetragonal scalenohedral. Color: Deep pinkish-brown Habit: Massive, granular. Crystals very rare and small, equant (pseudo-octahedral) in habit. Cleavage: […]
LEPIDOMELANE
LEPIDOMELANE See “Biotite”
LIZARDITE
LIZARDITE See “Serpentine”
LIMONITE
LIMONITE See “Goethite”
LAPIS LAZULI
LAPIS LAZULI See “Haüyne”
LEUCITE
LEUCITE Leucite – K(AlSi2O6) – is a tectosilicate of the Feldspathoid Group, constituting an important alkaline rock forming mineral. Leucite itself is not mined, but alkaline rocks as a whole can be used in the glass and ceramics industries as fluxes, for example. Leucite crystallizes in the cubic system in volcanic rocks at high temperatures […]
LEPIDOLITE
LEPIDOLITE Lepidolite is a rare phyllosilicate, restricted to litiniferous granitic pegmatites. May constitute an ore of Li, Cs and Rb. The name “lepidolite” as a mineral was discredited in 1989 and today it is just a generic name used for lithiniferous micas that make up a Series composed of Polylithionite (KLi2Al(Si4O10)(F,OH)2) – Trilithionite – (K(Li1,5 […]
LAWSONITE
LAWSONITE Lawsonite – CaAl2(Si2O7)(OH)2.H2O – is a very rare sorosilicate, typical of very specific metamorphic rocks. It has no economic importance. It is classified in the Lawsonite Group, has an Al analogue (cortesognoite) and has a variety with Cr. 1. Characteristics Crystal system: Orthorhombic bipiramidal. Color: Colorless, white, greyish blue, pale blue. Habit: Prismatic to […]