Guettardite is a rare

arsenic Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is not ...

antimony Antimony is a chemical element; it has chemical symbol, symbol Sb () and atomic number 51. A lustrous grey metal or metalloid, it is found in nature mainly as the sulfide mineral stibnite (). Antimony compounds have been known since ancient t ...

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

sulfosalt mineral Sulfosalt minerals are sulfide minerals with the general formula , where *A represents a metal such as copper, lead, silver, iron, and rarely mercury, zinc, vanadium *B usually represents semi-metal such as arsenic, antimony, bismuth, and rarely ...

with the chemical formula . It forms gray black metallic prismatic to acicular crystals with

monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three Vector (geometric), vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in t ...

symmetry. It is a

dimorph In crystallography, polymorphism is the phenomenon where a compound or element can crystallize into more than one crystal structure. The preceding definition has evolved over many years and is still under discussion today. Discussion of the defi ...

of the

triclinic class=skin-invert-image, 180px, Triclinic (a ≠ b ≠ c ≠ a and α, β, γ, 90° pairwise different) In crystallography, the triclinic (or anorthic) crystal system is one of the seven crystal systems. A crystal system is described by three b ...

twinnite.

Discovery and occurrence

It was first described in 1967 for an occurrence in the Taylor Pit,

Madoc Madoc ab Owain Gwynedd (also spelled Madog) was, according to folklore, a Welsh prince who sailed to the Americas in 1170, over 300 years before Christopher Columbus's voyage in 1492. According to the story, Madoc was a son of Owain Gwynedd w ...

Hastings County Hastings County is a county and census division of the Canadian province of Ontario. Geographically, it is located on the border of Eastern Ontario and Central Ontario. Hastings County is the second-largest county in Ontario, after Renfrew C ...

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

, Canada. It was named for French naturalist

Jean-Étienne Guettard Jean-Étienne Guettard (22 September 1715 – 7 January 1786), was a French naturalist and mineralogist. He was born at Étampes, near Paris. In boyhood, he gained a knowledge of plants from his grandfather, who was an apothecary, and later ...

(1715–1786). It occurs in

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 ...

veins Veins () are blood vessels in the circulatory system of 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 those of the pulmonary and fetal c ...

within

marble Marble is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO3) or Dolomite (mineral), dolomite (CaMg(CO3)2) that have recrystallized under the influence of heat and pressure. It has a crystalline texture, and is ty ...

at the type locality in Modoc. It occurs associated with

pyrite The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue ...

sphalerite Sphalerite is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in Sedimentary exhalative deposits, sedimentary exhalative, Carbonate-hoste ...

wurtzite Wurtzite is a zinc and iron sulfide mineral with the chemical formula , a less frequently encountered Polymorphism (materials science), structural polymorph form of sphalerite. The iron content is variable up to eight percent.Palache, Charles, H ...

galena Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crysta ...

stibnite Stibnite, sometimes called antimonite, is a sulfide mineral, a mineral form of antimony trisulfide ( Sb2 S3). It is a soft, metallic grey crystalline solid with an orthorhombic space group. It is the most important source for the metalloid an ...

orpiment Orpiment, also known as ″yellow arsenic blende″ is a deep-colored, orange-yellow arsenic sulfide mineral with formula . It is found in volcanic fumaroles, low-temperature hydrothermal veins, and hot springs and may be formed through sublimatio ...

realgar Realgar ( ), also known as arsenic blende, ruby sulphur or ruby of arsenic, is an arsenic sulfide mineral with the chemical formula α-. It is a soft, sectile mineral occurring in monoclinic crystals, or in granular, compact, or powdery form, ...

enargite Enargite is a copper arsenic sulfosalt mineral with formula Cu3AsS4. It takes its name from the Greek word , "distinct". Enargite is a steel gray, blackish gray, to violet black mineral with metallic luster. It forms slender orthorhombic prisms a ...

tetrahedrite Tetrahedrite is a copper antimony sulfosalt mineral with formula: . It is the antimony endmember of the continuous solid solution series with arsenic-bearing tennantite. Pure endmembers of the series are seldom if ever seen in nature. Of the two, ...

, zinkenite, jordanite,

bournonite Bournonite, also ''axotomous antimony glance'',''Robert Jameson''. Manual of Mineralogy: containing an account of simple minerals, and also a description and arrangement of mountain rocks. — Edinburgh, Archibald Constable & Co., 1821. — 49 ...

, sterryite,

boulangerite Boulangerite or ''antimonbleiblende'' is an uncommon monoclinic orthorhombic sulfosalt mineral, lead antimony sulfide, formula Pb5Sb4S11. It was named in 1837 in honor of French mining engineer Charles Boulanger (1810–1849),http://www.mindat.o ...

, jamesonite and sartorite at Madoc. In addition to the type locality, it has been reported from the Brobdingnag mine, near Silverton,

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

; the Jas Roux deposit in

Hautes-Alpes Hautes-Alpes (; ; ) is a Departments of France, department in the Provence-Alpes-Côte d'Azur Regions of France, region of Southeastern France. It is located in the heart of the French Alps, after which it is named. Hautes-Alpes had a population ...

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

; from various marble quarries near

Seravezza Seravezza is a town and ''comune'' in the Province of Lucca, in northern Tuscany, Italy. It is located in Versilia, close to the Apuan Alps. Neighboring municipalities *Forte dei Marmi * Massa * Montignoso *Pietrasanta * Stazzema Patron saints S ...

Tuscany Tuscany ( ; ) is a Regions of Italy, region in central Italy with an area of about and a population of 3,660,834 inhabitants as of 2025. The capital city is Florence. Tuscany is known for its landscapes, history, artistic legacy, and its in ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

; a marble quarry in

Valais Valais ( , ; ), more formally, the Canton of Valais or Wallis, is one of the cantons of Switzerland, 26 cantons forming the Switzerland, Swiss Confederation. It is composed of thirteen districts and its capital and largest city is Sion, Switzer ...

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

and from Khaydarkan,

Fergana Valley The Fergana Valley (also commonly spelled the Ferghana Valley) in Central Asia crosses eastern Uzbekistan, southern Kyrgyzstan and northern Tajikistan. Encompassing three former Republics of the Soviet Union, Soviet republics, the valley is e ...

Alai Mountains The Alay or Alai Range (; ) is a mountain range that extends from the Tien Shan mountain range in Kyrgyzstan west into Tajikistan. It is part of the Pamir-Alay mountain system. The range runs approximately east to west. Its highest summit is Pik ...

Kyrgyzstan Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia lying in the Tian Shan and Pamir Mountains, Pamir mountain ranges. Bishkek is the Capital city, capital and List of cities in Kyrgyzstan, largest city. Kyrgyz ...

References

External links

Discovery of guettardite
in French Sulfosalt minerals Lead minerals Monoclinic minerals Minerals in space group 14 {{sulfide-mineral-stub

Discovery and occurrence

See also

References

External links