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Pyrite is used with flintstone and a form of tinder made of stringybark by the Kaurna people of South Australia, as a traditional method of starting fires. [17] Pyrite has been used since classical times to manufacture copperas (ferrous sulfate). Iron pyrite was heaped up and allowed to weather (an example of an early form of heap leaching ...
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]
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 ...
Pyrochlore (Na,Ca) 2 Nb 2 O 6 (OH,F) is a mineral group of the niobium end member of the pyrochlore supergroup. Pyrochlore is also a term for the crystal structure Fd 3 m.The name is from the Greek πῦρ, fire, and χλωρός, green because it typically turns green on ignition in classic blowpipe analysis.
Từ điển bách khoa Việt Nam (lit: Encyclopaedic Dictionary of Vietnam) is a state-sponsored Vietnamese-language encyclopedia that was first published in 1995. It has four volumes consisting of 40,000 entries, the final of which was published in 2005. [1] The encyclopedia was republished in 2011.
The Vietnamese Wikipedia initially went online in November 2002, with a front page and an article about the Internet Society.The project received little attention and did not begin to receive significant contributions until it was "restarted" in October 2003 [3] and the newer, Unicode-capable MediaWiki software was installed soon after.