Chemistry Reference Libraries

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2005-05-26 08:39:06

In geology, the mineral monazite is a reddish-brown phosphate containing rare earth metals and an important source of thorium, lanthanum, and cerium. It occurs usually in small isolated crystals. There are actually three different kinds of monazite, depending on relative elemental composition of the mineral: - monazite-Ce (Ce, La, Nd, Th, Y)PO4 - monazite-La (La, Ce, Nd)PO4 - monazite-Nd...

2005-05-26 08:36:17

Murdochite is a mineral combining lead and copper oxides. It was first discovered in 1953 in Arizona.

2005-05-26 08:35:42

Muscovite, also known as potash mica, is a phyllosilicate mineral of aluminium and potassium. It has a highly perfect basal cleavage yielding remarkably thin laminae (sheets), which are often highly elastic. Muscovite has a hardness of 2 - 2.25 and a specific gravity of 2.76 - 3. It can be colorless or tinted through grays, browns, greens, yellows, or rarely violet or red, and can be...

2005-05-26 08:34:39

Orpiment is a common monoclinic crystalline mineral - Chemical Composition: As2S3, arsenic trisulfide - Molecular Weight: 246.04 gm - Hardness: 1.5-2 - Optical refractive index: Biaxial (-), a=2.4, b=2.81, g=3.02 Orpiment is a mineral that is found world-wide, and occurs as a sublimation product in volcanic fumaroles, low temperature hydrothermal veins, hot springs and as a...

2005-05-26 08:33:21

Pentlandite is a iron-nickel sulfide, (Fe,Ni)9S8. Pentlandite usually has a Ni:Fe ratio of close to 1:1. It also contains minor cobalt. Pentlandite forms isometric crystals, but is normally found in massive granular aggregates. It is brittle with a hardness of 3.5 - 4 and specific gravity of 4.6 - 5.0 and is non-magnetic. It has a yellowish bronze color. Pentlandite is the chief ore of...

2005-05-25 19:15:16

In chemistry, a phosphate is a polyatomic ion or radical consisting of one phosphorus atom and four oxygen. In the ionic form, it carries a -3 formal charge, and is denoted PO43-. In a biochemical setting, a free phosphate ion in solution is called inorganic phosphate, to distinguish it from phosphates bound in the form of ATP, or perhaps in DNA or RNA. Inorganic phosphate is generally...

2005-05-25 11:47:57

Tin is a chemical element in the periodic table that has the symbol Sn (L. Stannum) and atomic number 50. This silvery, malleable poor metal that is not easily oxidized in air and resists corrosion is found in many alloys and is used to coat other metals to prevent corrosion. Tin is obtained chiefly from the mineral cassiterite where it occurs as an oxide. Notable characteristics Tin is a...

2005-05-25 11:39:14

Tincalconite is a mineral closely related to borax, and is a secondary mineral that forms if borax is allowed to dry. The crystal shape of borax does not change during the drying process. Its formula is Na2B4O5(OH)4 - 3H2O or Na2B4O7 - 5H2O. While most tincalconite is created by man through exposing borax to dry air, there are natural occurrences of tincalconite, like in Searles Lake,...

2005-05-25 11:21:05

Titanium is a chemical element in the periodic table that has the symbol Ti and atomic number 22. It is a light, strong, lustrous, corrosion-resistant (including resistance to sea water and chlorine) transition metal with a white-silvery-metallic color. Titanium is used in strong light-weight alloys (most notably with iron and aluminum) and its most common compound, titanium dioxide, is used in...

2005-05-25 11:16:17

The mineral topaz is a silicate of aluminium and fluorine with the chemical formula (AlF)2SiO4. It is orthorhombic and its crystals are mostly prismatic terminated by pyramidal and other faces, the basal pinacoid often being present. It has an easy and perfect basal cleavage and so gemstones or other fine specimens should be handled with care to avoid developing cleavage flaws. The fracture is...

Word of the Day
  • Nautical, the visiting and carousing of sailors in the Greenland ships.
This word is apparently from a confusion of two similar Dutch words: 'mallemerok,' a foolish woman, and 'mallemok,' a name for some persons among the crew of a whaling vessel.