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Pyrite cubic crystals on marl from Navajún, La Rioja, Spain (size: 95 by 78 millimetres [3.7 by 3.1 in], 512 grams [18.1 oz]; main crystal: 31 millimetres [1.2 in] on edge) Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold.
The group is named for its most common member, pyrite (fool's gold), which is sometimes explicitly distinguished from the group's other members as iron pyrite. Pyrrhotite (magnetic pyrite) is magnetic, and is composed of iron and sulfur , but it has a different structure and is not in the pyrite group.
Also, the mineral pyrite is both the most common and most abundant sulfide mineral in the Earth's crust. [6] If rocks containing pyrite undergo metamorphism, there is a gradual release of volatile components like water and sulfur from pyrite. [6] The loss of sulfur causes pyrite to recrystallize into pyrrhotite. [6]
Pressure oxidation is a process for extracting gold from refractory ore.. The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them.
Following the increasing of Internet usage in Vietnam, many online encyclopedias were published. The two largest online Vietnamese-language encyclopedias are Từ điển bách khoa toàn thư Việt Nam, a state encyclopedia, and Vietnamese Wikipedia, a project of the Wikimedia Foundation.
These include ε-FeOOH, which has an orthorhombic crystal structure, [10] a cubic pyrite-type polymorph with [11] or without losing hydrogen [12] and an ultradense hexagonal structure. [13] Goethite has the same crystal structure as diaspore, the analogous aluminium oxide-hydroxide mineral. Oxygen and hydroxide ions form a hexagonal close ...
Pyrithione is the common name of an organosulfur compound with molecular formula C 5 H 5 NOS, chosen as an abbreviation of pyridinethione, and found in the Persian shallot. [4] It exists as a pair of tautomers, the major form being the thione 1-hydroxy-2(1H)-pyridinethione and the minor form being the thiol 2-mercaptopyridine N-oxide; it crystallises in the thione form. [5]
The Vietnamese Wikipedia (Vietnamese: Wikipedia tiếng Việt) is the Vietnamese-language edition of Wikipedia, a free, publicly editable, online encyclopedia supported by the Wikimedia Foundation. Like the rest of Wikipedia, its content is created and accessed using the MediaWiki wiki software.