The mineral petzite, Ag₃ Au Te₂, is a soft, steel-gray

telluride mineral A telluride mineral is a mineral that has the telluride anion as a main component. Tellurides are similar to sulfides and are grouped with them in both the Dana and Strunz mineral classification systems.http://webmineral.com/strunz/II.shtml Webm ...

generally deposited by

hydrothermal Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with th ...

activity. It forms isometric crystals, and is usually associated with rare

tellurium Tellurium is a chemical element with the symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionally fou ...

and

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile met ...

minerals, often with

silver Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, whi ...

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

, and

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...

. The name comes from chemist W. Petz, who first analyzed the mineral from the type locality in Săcărâmb,

Transylvania Transylvania ( ro, Ardeal or ; hu, Erdély; german: Siebenbürgen) is a historical and cultural region in Central Europe, encompassing central Romania. To the east and south its natural border is the Carpathian Mountains, and to the west the Ap ...

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

in 1845. It was described by

Wilhelm Karl Ritter von Haidinger Wilhelm Karl Ritter von Haidinger (or Wilhelm von Haidinger, or most often Wilhelm Haidinger) (5 February 179519 March 1871) was an Austrian mineralogist. Early life Haidinger's father was the mineralogist Karl Haidinger (1756–1797), who died w ...

in 1845 and dedicated to W. Petz who had carried out the first analyses. It occurs with other tellurides in

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

gold deposits. It is commonly associated with native gold,

hessite Hessite is a mineral form of disilver telluride (Ag2Te). It is a soft, dark grey telluride mineral which forms monoclinic crystals. It is named after Germain Henri Hess (1802–1850). Hessite is found in the US in Eagle County, Colorado and in ...

, sylvanite,

krennerite Krennerite is an orthorhombic gold telluride mineral which can contain variable amounts of silver in the structure. The formula is AuTe2, but specimen with gold substituted by up to 24% with silver have been found ( u0.77Ag0.24e2). Both of the c ...

calaverite Calaverite, or gold telluride, is an uncommon telluride of gold, a metallic mineral with the chemical formula AuTe2, with approximately 3% of the gold replaced by silver. It was first discovered in Calaveras County, California in 1861, and was ...

altaite Altaite, or lead telluride, is a yellowish white mineral with an isometric crystal structure. Altaite is in the galena group of minerals as it shares many of properties of galena. Altaite has an unusually high density for a light-colored mineral. ...

, montbrayite,

melonite Melonite is a telluride of nickel; it is a metallic mineral. Its chemical formula is NiTe2. It is opaque and white to reddish-white in color, oxidizing in air to a brown tarnish. It was first described from the Melones and Stanislaus mine in ...

, frohbergite,

tetradymite Tetradymite is a mineral consisting of bismuth, tellurium and sulfide, Bi2 Te2 S, also known as telluric bismuth. If sulfur is absent the mineral is tellurobismuthite and the formula is then Bi2Te3. Traces of selenium are usually present. Crysta ...

rickardite Rickardite is a telluride mineral, a copper telluride (Cu7Te5) or Cu3-x (x = 0 to 0.36)Te2. It was first described for an occurrence in the Good Hope Mine, Vulcan district, Gunnison County, Colorado, US, and named for mining engineer Thomas Arthur ...

vulcanite Vulcanite is a rare copper telluride mineral. The mineral has a metallic luster, and has a green or bronze-yellow tint. It has a hardness between 1 and 2 on the Mohs scale (between talc and gypsum). Its crystal structure is orthorhombic. Vulcanit ...

and

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), lust ...

. Petzite forms together with

uytenbogaardtite The mineral uytenbogaardtite, Ag3AuS2, is a soft, greyish white sulfide mineral, occurring in hydrothermal Au-Ag-quartz veins. It occurs as tiny crystals, visible only with a microscope. It has a metallic luster and a hardness on the Mohs scale ...

(Ag₃AuS₂) and fischesserite (Ag₃AuSe₂) the uytenbogaardtite group.

References

Silver minerals Gold minerals Gold(I) compounds Telluride minerals Cubic minerals Minerals in space group 214 Minerals described in 1845 {{mineral-stub

See also

References