Difference between revisions of "Acanthite"

Latest revision as of 10:08, 8 December 2022

Acanthite (Argentite); Image credit John Betts

Description

A gray to black metallic mineral of Silver sulfide. Acanthite occurs in hydrothermal deposits and as a corrosion product of Silver. Large crystals of acanthite have been mined in Norway (Kongsberg), Mexico (Pachuca, Guanajuato, Zacatecas) and the U.S. (Nevada, Colorado, Montana). On silver, acanthite crystals can appear as black, shiny, acanthus-like leaflets. At temperatures above 173 C, acanthite is converted to Argentite.

Synonyms and Related Terms

acanthus

Physical and Chemical Properties

Luster = metallic
Streak = black
Cuts like lead; indistinct cleavage
Composition = Ag2S
CAS = 21548-73-2
Mohs Hardness = 2.0 - 2.5
Melting Point = 845 C
Density = 7.2 - 7.4 g/ml
Molecular Weight = 247.8

Risks

Sensitive to light.

Resources and Citations

WebMineral: Acanthite

Encyclopedia Britannica, http://www.britannica.com Comment: argentite" Accessed December 11, 2001, (gives conversion temperature as 91 C)

C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979 Comment: Gives conversion temperature (acanthite to argentite) as 173 C

@@ Line 1: / Line 1: @@
+[[File:Acanthite Webmineral.jpg|thumb|Acanthite (Argentite); Image credit [http://www.johnbetts-fineminerals.com/ John Betts]]]
 == Description ==
@@ Line 7: / Line 8: @@
 acanthus
-[[[SliderGallery rightalign|acanthite.jpg~Chemical structure]]]
+== Physical and Chemical Properties ==
-== Other Properties ==
+* Luster = metallic
+* Streak = black
+* Cuts like lead; indistinct cleavage
+* Composition = Ag2S
+* CAS = 21548-73-2
+* Mohs Hardness = 2.0 - 2.5
+* Melting Point = 845 C
+* Density = 7.2 - 7.4 g/ml
+* Molecular Weight = 247.8
-Luster = metallic  Streak = black  Cuts like lead; indistinct cleavage
+== Risks ==
-{| class="wikitable"
-|-
-! scope="row"| Composition
-| Ag2S
-|-
-! scope="row"| CAS
-| 21548-73-2
-|-
-! scope="row"| Mohs Hardness
-| 2.0 - 2.5
-|-
-! scope="row"| Melting Point
-| 845
-|-
-! scope="row"| Density
-| 7.2 - 7.4
-|-
-! scope="row"| Molecular Weight
-| mol. wt. = 247.8
-|}
-== Hazards and Safety ==
 Sensitive to light.
-Fisher Scientific: [http://www.fishersci.ca/msds2.nsf/0/31889AFD3B9E59BE85256CA50002F9DC/$file/MSDS-65918.html?open MSDS]
+==Resources and Citations==
-== Additional Information ==
-Mineralogy Database: [http://www.webmineral.com/data/Acanthite.shtml Acanthite]
-== Sources Checked for Data in Record ==
+* WebMineral: [http://webmineral.com/data/Acanthite.shtml#.Yl3fPujMK7M Acanthite]
-* ''Encyclopedia Britannica'', http://www.britannica.com  Comment: argentite"   [Accessed December 11, 2001 (gives conversion temperature as 91 C)
+* ''Encyclopedia Britannica'', http://www.britannica.com  Comment: argentite" Accessed December 11, 2001, (gives conversion temperature as 91 C)
-* C.W.Chesterman, K.E.Lowe, ''Audubon Society Field Guide to North American Rocks and Minerals'', Alfred A. Knopf, New York, 1979  Comment: Gives conversion temperature as 173 C
+* C.W.Chesterman, K.E.Lowe, ''Audubon Society Field Guide to North American Rocks and Minerals'', Alfred A. Knopf, New York, 1979  Comment: Gives conversion temperature (acanthite to argentite) as 173 C
 [[Category:Materials database]]