Demicheleite-(Br)
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Demicheleite-(Br)
Formula:
BiSBr
Colour:
Dark red to black
Lustre:
Sub-Metallic
Specific Gravity:
6.312 (Calculated)
Crystal System:
Orthorhombic
Name:
Originally described as demicheleite, but renamed demicheleite-(Br) after the approval of demicheleite-(Cl), a chlorine-dominant analogue. Honors Vincenzo de Michele (b. 1936), former curator of the Natural History Museum, Milan, Italy, and for its chemical composition.
Type Locality:
Isostructural with:
The Br analogue of demicheleite-(Cl) and demicheleite-(I). Unique combination of elements. The only Bi-Br mineral known. The other sulfide-bromide minerals are 'arzakite' and grechishchevite.
Unique Identifiers
Mindat ID:
32198
Long-form identifier:
mindat:1:1:32198:1
GUID
(UUID V4):
(UUID V4):
76d689a6-1e73-4cf7-9dda-8c4f78359b99
IMA Classification of Demicheleite-(Br)
Classification of Demicheleite-(Br)
2.FC.25
2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
F : Sulfides of arsenic, alkalies; sulfides with halide, oxide, hydroxide, H2O
C : With Cl, Br, I (halide-sulfides)
2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
F : Sulfides of arsenic, alkalies; sulfides with halide, oxide, hydroxide, H2O
C : With Cl, Br, I (halide-sulfides)
2.15.14.1
2 : SULFIDES
15 : Chlor-sulfides
2 : SULFIDES
15 : Chlor-sulfides
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
Symbol | Source | Reference |
---|---|---|
Dem-Br | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Demicheleite-(Br)
Sub-Metallic
Transparency:
Translucent
Colour:
Dark red to black
Streak:
Red
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
None observed
Density:
6.312 g/cm3 (Calculated)
Chemistry of Demicheleite-(Br)
Mindat Formula:
BiSBr
Elements listed:
Crystallography of Demicheleite-(Br)
Crystal System:
Orthorhombic
Class (H-M):
mmm (2/m 2/m 2/m) - Dipyramidal
Space Group:
Pnma
Cell Parameters:
a = 8.0424 Å, b = 9.8511 Å, c = 4.0328 Å
Ratio:
a:b:c = 0.816 : 1 : 0.409
Unit Cell V:
319.50 ų (Calculated from Unit Cell)
Morphology:
Type material: prismatic {110} and {210}, terminated by minor faces of another prism {011}, a pinacoid {010}, and a bipyramid {111}.
Crystal Structure
Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Show
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
View
CIF File Best | x | y | z | a | b | c
CIF File Best | x | y | z | a | b | c
Rotation
Stop | Start
Stop | Start
Labels
Console Off | On | Grey | Yellow
Console Off | On | Grey | Yellow
Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure
ID | Species | Reference | Link | Year | Locality | Pressure (GPa) | Temp (K) |
---|---|---|---|---|---|---|---|
0004679 | Demicheleite-(Br) | Demartin F, Gramaccioli C M, Campostrini I, Orlandi P (2008) Demicheleite, BiSBr, a new mineral from La Fossa crater, Vulcano, Aeolian Islands, Italy American Mineralogist 93 1603-1607 | 2008 | La Fossa crater, Vulcano, Aeolian Islands, Italy | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
d-spacing | Intensity |
---|---|
4.220 Å | (68) |
3.740 Å | (62) |
3.721 Å | (44) |
2.909 Å | (100) |
2.429 Å | (43) |
2.036 Å | (47) |
1.865 Å | (63) |
1.774 Å | (88) |
Geological Environment
Paragenetic Mode(s):
Paragenetic Mode | Earliest Age (Ga) |
---|---|
Stage 3a: Earth’s earliest Hadean crust | >4.50 |
11 : Volcanic fumarole minerals; reduced phases (see also #45) |
Type Occurrence of Demicheleite-(Br)
General Appearance of Type Material:
Well-formed, prismatic translucent crystals up to 0.5 mm in size.
Place of Conservation of Type Material:
Department of Structural Chemistry and Inorganic Stereochemistry, University of Milan, Italy, reference collection 2007-01.
Geological Setting of Type Material:
An active high-temperature fumarole, in an altered pyroclastic breccia.
Associated Minerals at Type Locality:
Synonyms of Demicheleite-(Br)
Demicheleite (in part)
Common Associates
Associated Minerals Based on Photo Data:
Related Minerals - Strunz-mindat Grouping
2.FC. | Demicheleite-(I) | BiSI |
2.FC.05 | Djerfisherite | K6(Fe,Cu,Ni)25S26Cl |
2.FC.05 | Thalfenisite | Tl6(Fe,Ni,Cu)25S26Cl |
2.FC.05 | Owensite | (Ba,Pb)6(Cu,Fe,Ni)25S27 |
2.FC.05 | Cu-djerfisherite | K6(Cu,Fe)25S26Cl |
2.FC.05 | Zoharite | (Ba,K)6(Fe,Cu,Ni)25S27 |
2.FC.05 | Gmalimite | K6◻Fe2+24S27 |
2.FC.10 | Bartonite | K6Fe20S26S |
2.FC.10 | Chlorbartonite | K6Fe24S26(Cl,S) |
2.FC.15a | Arzakite | Hg2+3S2(Br,Cl)2 |
2.FC.15a | Corderoite | Hg2+3S2Cl2 |
2.FC.15c | Grechishchevite | Hg2+3S2(Br,Cl,I)2 |
2.FC.15a | Lavrentievite | Hg2+3S2(Cl,Br)2 |
2.FC.15d | Radtkeite | Hg2+3S2ICl |
2.FC.15b | Kenhsuite | Hg2+3S2Cl2 |
2.FC.20a | Capgaronnite | AgHgClS |
2.FC.20c | Perroudite | Hg5Ag4S5(I,Br)2Cl2 |
2.FC.20b | Iltisite | HgAgSCl |
2.FC.20d | Hanauerite | AgHgSI |
2.FC.25 | Demicheleite-(Cl) | BiSCl |
Fluorescence of Demicheleite-(Br)
Not fluorescent
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Demicheleite-(Br)
mindat.org URL:
https://www.mindat.org/min-32198.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Demicheleite-(Br)
Localities for Demicheleite-(Br)
Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
Struck out - Mineral was erroneously reported from this locality.
Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).
All localities listed without proper references should be considered as questionable.
All localities listed without proper references should be considered as questionable.
Czech Republic | |
| Dalibor Matýsek |
Dalibor Matýsek | |
Italy (TL) | |
| Demartin et al. (2008) |
Quick NavTopAbout Demicheleite-(Br)Unique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Chemistry Crystallography Crystal StructureX-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsCommon AssociatesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
La Fossa crater, Vulcano Island, Lipari, Eolie Islands, Metropolitan City of Messina, Sicily, Italy