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Latest Mineral Stories

Theory Of The Formation Of Crystals Is Complete Again
2013-02-19 14:21:47

Eindhoven University of Technology Exactly how a crystal forms from solution is a problem that has occupied scientists for decades. Researchers at Eindhoven University of Technology (TU/e), together with researchers from Germany and the USA, are now presenting the missing piece. This classical theory of crystal formation, which occurs widely in nature and in the chemical industry, was under fire for some years, but is saved now. The team made this breakthrough by a detailed study of the...

2012-06-26 10:26:11

Mineral evolution posits that Earth's near-surface mineral diversity gradually increased through an array of chemical and biological processes. A dozen different species in interstellar dust particles that formed the solar system have evolved to more than 4500 species today. Previous work from Carnegie's Bob Hazen demonstrated that up to two thirds of the known types of minerals on Earth can be directly or indirectly linked to biological activity. Now Hazen has turned his focus specifically...


Latest Mineral Reference Libraries

28_3f12abda63415a07ee5b6c5d30ef8239
2005-05-26 12:17:18

Aragonite is a polymorph of the mineral calcite, both having the chemical composition CaCO3. Its structure differs from calcite and leads to a different crystal shape, an orthorhombic system with acicular crystals. By repeated twinning pseudo-hexagonal forms result. It may be columnar or fibrous, occasionally in branching stalactitic forms called flos-ferri (flowers of iron) from their association with the ores at the Carthinian iron mines. The type location for aragonite is Molina de...

28_65bb1e3b5e8109d8123acc847d3660d1
2005-05-26 12:13:03

Augite is a mafic mineral described chemically as (Ca, Na)(Mg, Fe, Al)(Al, Si)2O6 or calcium sodium magnesium iron aluminium silicate. Structurally, it is a solid solution of the pyroxene group which also contains diopside and hedenbergite. The crystals are monoclinic and prismatic. It is found in igneous rocks such as gabbros and basalts, and in metamorphic rocks from hydrothermal vents. Occasional specimens have a shiny appearance that give rise to the mineral's name, which is from the...

28_d2c55a2f2b1619323d50ee8c6db10bb5
2005-05-26 11:56:59

Celestite (SrSO4) is a mineral consisting of strontium sulfate. The mineral is also known as celestine and is named for its occasional delicate blue color. Celestite occurs as crystals, and also in compact massive and fibrous forms. It is mostly found in sedimentary rocks, often associated with the minerals gypsum, anhydrite, and halite. The mineral is found worldwide, usually in small quantities. Pale blue crystal specimens are found in Madagascar.

28_c88e07ed3311d042dca4ab65074d905b
2005-05-26 11:13:48

Colemanite (Ca2B6O11·5H2O) is a borate mineral found in evaporite deposits. Colemanite is a secondary mineral that forms when borax is deposited, and then regularly covered with boron containing water. The boron remains after the water evaporates, and the boron and borax eventually form other minerals as for example Colemanite. It was named after William T. Coleman (1824-1893), owner of the mine where it was first found.

28_f61a133ae4dae9735d482110e636dcfe
2005-05-26 10:59:49

Galena is a lead ore. This article describes Galena's mineral properties. In its chemically purified form, Galena is known as Lead Sulfide; refer to that article for chemical and industrial uses. Galena is one of the most abundant and widely distributed sulfide minerals, and is the most common ore of lead. Crystals are usually cubic, sometimes octahedral. It is often associated with the minerals sphalerite and fluorite. Galena deposits sometimes contain significant amounts of silver as an...

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Word of the Day
sough
  • A murmuring sound; a rushing or whistling sound, like that of the wind; a deep sigh.
  • A gentle breeze; a waft; a breath.
  • Any rumor that engages general attention.
  • A cant or whining mode of speaking, especially in preaching or praying; the chant or recitative characteristic of the old Presbyterians in Scotland.
  • To make a rushing, whistling, or sighing sound; emit a hollow murmur; murmur or sigh like the wind.
  • To breathe in or as in sleep.
  • To utter in a whining or monotonous tone.
According to the OED, from the 16th century, this word is 'almost exclusively Scots and northern dialect until adopted in general literary use in the 19th.'
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