DESCLOIZITE
DESCLOIZITE Descloizite – PbZn(VO4)(OH) – is a fairly rare vanadate, characteristic of oxidation zones of Pb and Zn sulfide deposits. It is part of base metal ores, but is never the main ore mineral of the deposit. On the rare occasions when it occurs in larger quantities, it is used as a V ore. A […]
DELAFOSSITE
DELAFOSSITE Delafossite – CuFeO2 -is a very rare oxide, characteristic as a secondary mineral in some oxidized Cu ores. It does not constitute an ore. It is classified in the Delafossite Group. There is a variety with a mixture of clay minerals. It is weakly magnetic. 1. Characteristics Crystal system: Trigonal scalenohedral. […]
DJURLEITE
DJURLEITE Djurleite – Cu31S16 – is a fairly common sulfide found in copper ores. The planetary abundance of copper and sulfur, their wide distribution, and the high reactivity of the two elements have generated nearly 300 different mineral species that contain them. There are nine different minerals formed only by Cu + S. Copper sulfide […]
DAVYNE
DAVYNE Davyne – (Na,K)6Ca2(Al6Si6O24)(Cl2,SO4) – is an extremely rare tectosilicate, typical of volcanic lavas and ejecta containing leucite. It is not an ore. It is classified in the Feldspathoid Group, within the Cancrinite Group. It can be considered a Cl-rich cancrinite. There is a CO2-free variety. It is extremely similar to quadridavyna; differentiation requires analytical […]
DIOPTASE
DIOPTASE Dioptase – CuSiO3.H2O – is a very rare cyclosilicate, a secondary Cu mineral that can be found in some oxidized ores of Cu, Pb, and Zn. Aesthetic pieces fetch very high prices in the collector’s mineral market. It is sometimes used as a gemstone, and its powder provides a green pigment for paints. Famous […]
DIGENITE
DIGENITE Digenite – Cu9S5 – is a fairly common sulfide, an important Cu ore. The planetary abundance of copper and sulfur, their wide distribution, and the high reactivity of the two elements have generated nearly 300 different mineral species that contain them. There are nine different minerals formed only by Cu + S. Copper sulfide […]
DUMORTIERITE
DUMORTIERITE Dumortierite – (Al,Fe3+)7(SiO4)3(BO3)O3 – is a fairly rare nesosilicate, characteristic of some types of metamorphic rocks. It is used in the manufacture of porcelain. Macroscopically, it can be confused with sodalite and has been used as an imitation of lapis lazuli. Dumortierite is classified in the Dumortierite Supergroup, is isostructural with magnesiodumortierite, and is […]
DIASPORE
DIASPORE Diaspore -AlO(OH) – is a very common hydroxide and—along with gibbsite and boehmite—one of the main components of bauxite, the most important aluminum ore. It is classified within the Diaspore Group and is isomorphous with boehmite. It typically contains Fe, Mn, Cr, and Si and is cryptocrystalline; consequently, microscopy is not the appropriate analytical […]
DOLOMITE
DOLOMITE Dolomite – Ca,Mg(CO3)2 – is a very common carbonate, an important rock former and with a number of industrial applications, although much less so than calcite. The number of uses for a given limestone rock is inversely proportional to its magnesium content. Dolomite is the most common carbonate after calcite. Unlike calcite, it never […]
DOMEYKITE
DOMEYKITE Domeykite or Domeykite-α – Cu3As – is a rare arsenide. It participates in complex Cu and Ag ores with As. It is dimorphic with β-domeykite, which is a Cu-deficient domeykite, macroscopically visually indistinguishable from domeykite and which transitions to α-domeykite at approximately 225ºC. Domeykite is isotypic with dienerite and may contain Sb and S. […]