Columbite

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Columbite from Madagascar

Columbite (Columbeisen, Niobit) is not an independent mineral , but a collective name for a mixed crystal from the series columbite (Fe) , columbite (Mg) and columbite (Mn) which is not specified . The mixed crystals crystallize like the terminal minerals of this series in the orthorhombic crystal system . These show the following color and chemistry :

  • Columbite- (Fe) (formerly ferrocolumbite ): brownish-gray-white; Fe 2+ Nb 2 O 6
  • Columbite (Mg) (formerly magnocolumbite or magnesiocolumbite ): brownish-black; MgNb 2 O 6
  • Columbite- (Mn) (formerly Manganocolumbit ): brownish-black to black; Mn 2+ Nb 2 O 6

The columbite series also forms a mineral series with the mineral tantalite and is registered as a group name with the International Mineralogical Association (IMA). The mixed crystals (and ores) in this series are known as coltan .

Etymology and history

The occurrence of columbite in the United States was known through a sample from Haddam , Connecticut , which was believed to have come from John Winthrop, Jr. (1606–1676), the first governor of the Colony of Connecticut and an avid mineral collector. Together with 600 other samples, it was part of a gift from his grandson of the same name (John Winthrop, 1681–1747) to Hans Sloane , President of the Royal Society of the United Kingdom , on the occasion of his acceptance as a Fellow of the Royal Society in 1737.

In 1801, Charles Hatchett discovered a new element ( niobium ) in this sample and named it Columbium , after Christopher Columbus (Latinized Christophorus Columbus ), the discoverer of America.

It was not until 1844 that the German chemist Heinrich Rose was able to prove that columbite contains two elements, namely niobium and tantalum .

Education and Locations

Columbite are usually found in granite - rocks (pegmatites), among others

use

Columbite ore is an important for the extraction of niobium (named as niobium up to the 1950s was called -year columbium) and tantalum and steel - alloys added to increase the strength.

See also

Individual evidence

  1. ↑ a b c Mineral Atlas: Columbit- (Fe) , Mineralienatlas: Columbit- (Mg) and Mineralienatlas: Columbit- (Mn) (Wiki)
  2. ↑ a b c IMA / CNMNC List of Mineral Names - Columbite (English, PDF 1.8 MB; pp. 62–63)
  3. ↑ IMA / CNMNC mineral list (March 2007; p. 59) (PDF, 892 kB; engl.)
  4. ^ John Winthrop: Art. V. Selections from an Ancient Catalog of objects of Natural History, formed in New England more than one hundred years ago . Baldwin, Cradock, and Joy. 1844. Retrieved February 12, 2015: “... (p.282 :) Mr. Winthrop was grandson of the first governor of Connecticut, great grandson of the first governor of Massachusetts ( Mr. Winthrop was grandson of the first governor of Connecticut , Great-grandson of the first governor of Massachusetts ) ... (p.290 :) A black mineral ... Is this the Columbite? ... it appeared that it had been sent ... to Sir Hans Sloane, by Mr. Winthrop of Massachusetts. (A black mineral ... is this the columbite? ... apparently it was ... sent to Hans Sloane, by Mr. Winthrop of Massachusetts. ) ... '"
  5. ^ Robert Jameson: System of Mineralogy, Vol. II . Bell and Bradfute (et al.). 1805. Retrieved on February 15, 2015: “... Mr Hatchett found it to contain a metal, which, from its properties, could not be referred to any hitherto known; hence he was of opinion that it should be considered as a new genus, to which he gave the name Columbium, in honor of the discoverer of America . (Mr. Hatchett realized that it contained a metal that, by virtue of its properties, could not be assigned to any previously known; therefore he was of the opinion that it should be considered as a new species, which he named Columbium in honor of the discoverer of America .) ... "

Web links

Commons : Columbite  - collection of images, videos and audio files