Fletcherite: Properties and Occurrences Fletcherite is a rare thiospinel sulfide mineral with formula Cu(Ni, Co)2S4. It is an isometric-hexoctahedral steel-gray mineral containing cobalt, copper, nickel, and sulfur. It is…
Fichtelite: Properties and Occurrence Fichtelite is a rare white mineral found in fossilized wood from Bavaria. It is a rare white monoclinic mineral found in fossilized wood from Bavaria.…
Fettelite: Properties and Occurrences Fettelite, also known as sanguinite, is a mercury-sulfosalt mineral with the chemical formula Ag16HgAs4S15. It is a rare Silver Mercury Arsenic Sulfosalt forming silvery to…
Properties of Angles of a Triangle 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…
Orthorhombic Ferroselite Orthorhombic ferroselite and its isometric polymorph dzharkenite are iron selenides of general formula FeSe2 precipitated under reducing conditions in anoxic environments. It is an orthorhombic-dipyramidal…
Ferropericlase Ferropericlase or magnesiowüstite is a magnesium/iron oxide [(Mg, Fe)O] that is interpreted to be one of the main constituents of the Earth’s lower mantle together…
Order of a Surd Order of a Surd Definitions of surds: A root of a positive real quantity is called a surd if its value cannot be exactly determined.…
Post-perovskite (pPv) Post-perovskite (pPv) is a high-pressure phase of magnesium silicate (MgSiO3). It is a high-pressure phase of several minerals, including magnesium silicate. It is composed of…
Ilmenite: Properties and Ooccurrences Ilmenite is the titanium-iron oxide mineral with the idealized formula FeTiO3. It is a common accessory mineral in igneous rocks, sediments, and sedimentary rocks in many…
Ferronigerite-2N1S Ferronigerite-2N1S is an iron, tin, alumino-hydroxide mineral that naturally occurs around sillimanite-quartz veins. It is very rarely found in gem-quality, cut-able material. Related to, and…
Induction Proof – Problems with Solutions Induction Proof – Problems with Solutions Mathematical induction is a technique for proving a statement – a theorem, or a formula — that is asserted…
Ferro-actinolite Ferro-actinolite is the ferrous iron-rich endmember of the actinolite-tremolite continuous solid solution series of the double chain calcareous amphibole group of inosilicate minerals. It is…