Argentite

Argentite

Argentite was primarily treated as a mineral belonging to the galena group, cubic silver sulfide (Ag2S), occasionally found as uneven cubes and octahedra, but more often as dendritic or earthy masses, with a blackish lead-grey color and metallic lustre. All these forms are structurally not argentite, but its monoclinic polymorph, acanthite. Due to instability in normal air temperature, the IMA commision decided to reject this mineral, which now is a discredited mineral species. The cubic cleavage, which is so prominent a feature in galena, here present only in traces. The mineral is perfectly sectile and has a shining streak; hardness 2.5, specific gravity 7.3. It occurs in mineral veins, and when found in large masses, as in is Mexico and in the Comstock Lode in Nevada, it forms an important ore of silver. The mineral was mentioned 1529 by G. Agricola, but the name argentite (from the Lat. "argentum", silver) was not used till 1845 and is due to W. Haidinger. Old names for the species are Glaserz, silver-glance and vitreous silver. A related Cu-rich mineral occurring i.e. in Jalpa, Mexico, is known as jalpaite.

Acanthite, also Ag2S, crystallizes in the monoclinic system and is the stable form below 177oC. As argentite cools below that temperature its cubic form is distorted to the monclinic form of acanthite. Thus, only acanthite is stable in normal air temperature and only this form is beeing found.

References

* [http://www.mindat.org/min-10.html Mindat.org]
* [http://www.webmineral.com/data/Argentite.shtml Webmineral.org]
*1911


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  • argentite — [ arʒɑ̃tit ] n. f. • 1869; de argent ♦ Minér. Minerai d argent (sulfure), gris noir. ⇒ argyrose. ● argentite nom féminin Synonyme de argyrose. ● argentite (synonymes) nom féminin Synonymes …   Encyclopédie Universelle

  • Argentite — Ar gen*tite, n. [L. argentum silver.] (Min.) Sulphide of silver; also called {vitreous silver}, or {silver glance}. It has a metallic luster, a lead gray color, and is sectile like lead. [1913 Webster] …   The Collaborative International Dictionary of English

  • argentite — s. f. [Mineralogia] Mineral monométrico, sulfureto de prata, um dos mais preciosos e ricos minérios de prata.   ♦ Grafia no Brasil: argentita …   Dicionário da Língua Portuguesa

  • argentite — [är′jəntīt΄] n. [< L argentum (see ARGENT) + ITE1] native silver sulfide, a lead gray cubic mineral, Ag2S, that is an important ore of silver …   English World dictionary

  • Argentite — Acanthite Acanthite Catégorie II : sulfures et sulfosels Acanthite Abrahamschacht, Freiberg, Saxe Allemagne (4x3cm) …   Wikipédia en Français

  • Argentite-β — Acanthite Acanthite Catégorie II : sulfures et sulfosels Acanthite Abrahamschacht, Freiberg, Saxe Allemagne (4x3cm) …   Wikipédia en Français

  • argentite — argentitas statusas T sritis chemija apibrėžtis Mineralas. formulė Ag₂S atitikmenys: angl. argentite; vitreous silver rus. аргентит; серебряный блеск …   Chemijos terminų aiškinamasis žodynas

  • argentite — argentitas statusas T sritis chemija apibrėžtis Anijonas, turintis centrinį Ag(I) atomą. atitikmenys: angl. argentite rus. аргентит …   Chemijos terminų aiškinamasis žodynas

  • argentite — noun Date: circa 1868 a dark gray or black mineral of metallic luster that consists of native sulfide of silver and is a valuable silver ore …   New Collegiate Dictionary

  • argentite — /ahr jeuhn tuyt /, n. a dark lead gray sectile mineral, silver sulfide, Ag2S, occurring in crystals and as formless aggregates: an important ore of silver. [1830 40; ARGENT + ITE1] * * * …   Universalium

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