Science

Dumortierite is a fibrous variably colored aluminum boro-silicate mineral, Al7BO3(SiO)3O3. It is a fibrous aluminum boro-silicate mineral that occurs in various colors. It is a…

Duftite is a relatively common arsenate mineral with the formula CuPb(AsO4)(OH), related to conichalcite. The color of duftite gives it its great note of distinction.…

Drysdallite is a rare molybdenum selenium sulfide mineral with formula Mo(Se, S)2. It is a rare, opaque molybdenum selenium sulfide mineral. It crystallizes in the…

Donnayite-(Y) is a rare-earth carbonate mineral containing the rare-earth metal yttrium. It was first discovered in 1978 at Mont St-Hilaire, Quebec. It can be found…

Domeykite is a copper arsenide mineral, Cu3As. It is a semi-metal alloy of copper and arsenic. It crystallizes in the isometric system, although crystals are…

Dolomite is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally CaMg(CO3)2. It is a common rock-forming mineral. It is rarely found in modern…

The definitions of a plane curve like circle, parabola, ellipse etc. are based on the concept of the locus. For example, the locus of points…

Dollaseite-(Ce) is an epidote found in metamorphosed limes times and is very rare. It is a sorosilicate end-member epidote mineral and was discovered by Gajer…

Dmitryivanovite is a natural mineral composed of calcium, aluminum, and oxygen, with the molecular formula CaAl2O4. It was reported in 2009 in a calcium-aluminum-rich inclusion…

Djurleite is a copper sulfide mineral of secondary origin with formula Cu31S16 that crystallizes with monoclinic-prismatic symmetry. It is typically massive in form but does…

Introduction of locus – math: The concept of locus – math is very important in analytical geometry. The definitions of a plane curve like circle,…

Djerfisherite is an alkali copper–iron sulfide mineral and a member of the djerfisherite group. It is an isometric-hexoctahedral mineral containing chlorine, copper, iron, nickel, potassium,…