Francevillite: Properties and Occurrences Francevillite is a uranyl-group vanadate mineral in the tyuyamunite series. Its chemical formula is (Ba, Pb)(UO2)2V2O8·5(H2O). It is an orthorhombic-dipyramidal mineral containing barium, hydrogen, lead,…
Fraipontite: Properties and Occurrences Fraipontite is a zinc-aluminum silicate mineral with a formula of (Zn, Al)3(Si, Al)2O5(OH)4. It is a member of the kaolinite-serpentine mineral group and occurs as…
Fourmarierite Fourmarierite is a secondary uranium-lead mineral. It was named for the Belgian geologist Paul Fourmarier (1877–1970). It is a mineral consisting of a hydrous oxide…
Direct Variation in Mathematics “Variation” defines a concept that deals with variability in mathematics. Variation is defined by any change in some quantity due to change in another. We…
Fougèrite: Properties and Occurrences Fougèrite is a relatively recently described naturally occurring green rust mineral. It is a trigonal clay mineral that is chemically and structurally related to green…
Forsterite: Properties and Occurrences Forsterite (Formula- Mg2SiO4) is the magnesium-rich end-member of the olivine solid solution series. It is a crystalline magnesium silicate. It is best known for having,…
Fornacite: Properties and Occurrence Fornacite is a rare lead, copper chromate arsenate hydroxide mineral with the formula: Pb2Cu(CrO4)(AsO4)(OH). It is a monoclinic-prismatic mineral containing arsenic, chromium, copper, hydrogen, lead,…
Classification of Triangles on the Basis of their Angles Triangle is a plane figure with three straight sides and three angles. The three angles always add to 180°. The vertex is a corner of the…
Fluorite: Properties and Occurrence Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It is a halide mineral composed of calcium fluoride. It crystallizes in isometric…
Fluorellestadite Fluorellestadite is a rare nesosilicate of calcium, with sulfate and fluorine, with the chemical formula Ca10(SiO4)3(SO4)3F2. It is a rare nesosilicate of calcium, with sulfate…
Fluororichterite Fluororichterite is a rare amphibole with formula Na(NaCa)Mg5Si8O22F2. It was recognized by the International Mineralogical Association in 1994. Its name is derived from its fluorine…
Classification of Triangles on the Basis of their Sides Triangle is a plane figure with three straight sides and three angles. The three angles always add to 180°. The vertex is a corner of the…