LEPIDOCROCITE
LEPIDOCROCITE Lepidocrocite – γ-FeO(OH) – is a very common hydroxide that can occur in association with various types of ores, especially oxidized iron ores and those containing iron sulfides. Lepidocrocite is a polymorph of goethite and feroxyhyte. It is a component of “limonite” and may contain Mn and Co, as well as various other impurities, […]
LAURITE
LAURITE Laurite – RuS2 – is a rather rare sulfide, characteristic of ultramafic intrusions containing platinum-group elements. It is an ore of Ru. It is classified within the Pyrite Group, in the Ehrlichmanite-Laurite Series. It may contain Os, Rh, Ir, and Fe. 1. Characteristics Crystal system: Cubic diploidal. Color: Black. Habit: […]
LIBETHENITE
LIBETHENITE Libethenite – Cu2(PO4)(OH) – is a rare phosphate, typically a secondary mineral in Cu occurrences. It is part of Cu ores, but is just one of many sporadically occurring secondary minerals in the deposit. Pieces with idiomorphic crystals fetch high prices, several hundred US dollars, in the collector’s mineral market. It is classified in […]
LINARITE
LINARITE Linarite – PbCu(SO4)(OH)2 – is a relatively rare sulfate, one of several blue secondary copper minerals. It forms part of oxidized copper, lead, and zinc ores, but is not a major ore mineral. It is classified in the four-member Linarite-Chenite Group. 1. Characteristics Crystal system: Monoclinic prismatic. Color: Deep, intense […]
LUDWIGITE
LUDWIGITE Ludwigite – Mg2Fe3+(BO3)O2 – is a rare borate, member of the Ludwigite Group, dimorph of magnesiohulsite and the magnesium analogue of Vonsenite and Marinaite. It has two varieties, with Al and with Sn (up to 12.0% w/w). Ludwigite is ferromagnetic and slowly soluble in acids. 1. Characteristics Crystal system: Orthorhombic dipyramidal. […]
LINNAEITE
LINNAEITE Linnaeite – Co2+Co3+2S4 – is a rare sulfide that occurs in Co and Ni ores. It is classified in the Linnaeite Subgroup. It forms a series with polydymite and another series with siegenite. Common impurities are Ni, Cu, Fe, and Se. It is possible that some Ni-rich reports of this mineral refers to the […]
LÖLLINGITE
LÖLLINGITE Löllingite – FeAs2 – is a relatively rare arsenide, usually found in small quantities in deposits containing arsenic minerals. It does not serve as a primary ore of arsenic, at most acts as a secondary one. It is classified within the Löllingite Group and forms a series with safflorite. It may contain Bi, Sb, […]
LEAD
LEAD Native lead is a fairly rare native element, recorded in just over 200 occurrences worldwide. It has also been recorded on the moon. It is not an ore due to its rarity. It belongs to the Copper Group, along with copper, gold, maldonite (Au2Bi), and silver. When it forms crystals, they are octahedrons, cubes, […]
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: […]