Edge Rewrite
// HTMLRewriter · presentation

This page was redesigned at the edge.

Cloudflare fetched the original article and streamed it through HTMLRewriter to apply an entirely new visual system without rebuilding the source page.

// request.cf · coarse context

A page that knows where it met you.

Only coarse request metadata is shown. This demo does not display or persist visitor IP addresses.

Country
US
Cloudflare location
CMH
Connection
HTTP/2
Language
Not provided

Ray ID: a2526db04ededf63

Jump to content

// Workers AI · dad joke modeWhat did Guettardite say? I'm a mineral attraction.

From Wikipedia, the free encyclopedia
Guettardite
General
CategorySulfosalt mineral
FormulaPb(Sb,As)2S4
IMA symbolGue[1]
Strunz classification2.HC.05a
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/a
Unit cella = 20.17, b = 7.94
c = 8.72 [Å]; β = 101.12°; Z = 8
Identification
ColorGrayish black; white with reddish internal reflections in polished section
Crystal habitAcicular crystals and anhedral grains
TwinningPolysynthetic twinning on {100}
CleavagePerfect on {001}
FractureConchoidal
TenacityVery brittle
Mohs scale hardness4
LusterMetallic
StreakBrown
DiaphaneityOpaque
Specific gravity5.2
PleochroismRelatively strong
References[2][3][4]

Guettardite is a rare arsenic-antimony lead sulfosalt mineral with the chemical formula Pb(Sb,As)2S4. It forms gray black metallic prismatic to acicular crystals with monoclinic symmetry. It is a dimorph of the triclinic twinnite.

Discovery and occurrence

[edit]

It was first described in 1967 for an occurrence in the Taylor Pit, Madoc, Hastings County, Ontario, Canada. It was named for French naturalist Jean-Étienne Guettard (1715–1786).[2]

It occurs in hydrothermal veins within marble at the type locality in Modoc. It occurs associated with pyrite, sphalerite, wurtzite, galena, stibnite, orpiment, realgar, enargite, tetrahedrite, zinkenite, jordanite, bournonite, sterryite, boulangerite, jamesonite and sartorite at Madoc.[3]

In addition to the type locality, it has been reported from the Brobdingnag mine, near Silverton, Colorado; the Jas Roux deposit in Hautes-Alpes, France; from various marble quarries near Seravezza, Tuscany, Italy; a marble quarry in Valais, Switzerland and from Khaydarkan, Fergana Valley, Alai Mountains, Kyrgyzstan.[2][3]

See also

[edit]

References

[edit]
  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. 1 2 3 "Guettardite". mindat.org. Hudson Institute of Mineralogy. Retrieved October 10, 2020.
  3. 1 2 3 Handbook of Mineralogy
  4. Webmineral data
[edit]