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Demicheleite-(I)

A valid IMA mineral species
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About Demicheleite-(I)Hide

Formula:
BiSI
Colour:
dark red to black
Lustre:
Sub-Metallic
Specific Gravity:
6.411 (Calculated)
Crystal System:
Orthorhombic
Name:
Named for its relationship to demicheleite-(Br) and demicheleite-(Cl), with dominant I. The root name honors Vincenzo de Michele (b. 1936), former curator of the Natural History Museum, Milan, Italy.
I-dominant analogue of demicheleite-(Br) and demicheleite-(Cl). Unique combination of elements. The only Bi-I mineral known (compare the experimentally obtained phase: Unnamed (Pb-Bi iodide)). The other sulfide-iodide minerals are mutnovskite, perroudite, and radtkeite.


Unique IdentifiersHide

Mindat ID:
39683
Long-form identifier:
mindat:1:1:39683:3

Similar NamesHide

Demicheleite
Demicheleite-(Br)A valid IMA mineral speciesBiSBr
Demicheleite-(Cl)A valid IMA mineral speciesBiSCl

IMA Classification of Demicheleite-(I)Hide

Classification of Demicheleite-(I)Hide

2.FC.

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)

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
Dem-IIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of Demicheleite-(I)Hide

Sub-Metallic
Transparency:
Translucent
Colour:
Dark red to black
Streak:
Brown
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
None observed
Density:
6.411 g/cm3 (Calculated)

Chemistry of Demicheleite-(I)Hide

Mindat Formula:
BiSI
Element Weights:
Element% weight
Bi56.796 %
I34.490 %
S8.715 %

Calculated from ideal end-member formula.

Crystallography of Demicheleite-(I)Hide

Crystal System:
Orthorhombic
Class (H-M):
mmm(2/m2/m2/m) - Dipyramidal
Space Group:
Pnma
Cell Parameters:
a = 8.4501(7) Å, b = 10.1470(9) Å, c = 4.1389(4) Å
Ratio:
a:b:c = 0.833 : 1 : 0.408
Unit Cell V:
354.88 ų (Calculated from Unit Cell)
Morphology:
Prismatic, with dominant forms {110} and {111}.

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 3a: Earth’s earliest Hadean crust>4.50
11 : Volcanic fumarole minerals; reduced phases (see also #45)

Type Occurrence of Demicheleite-(I)Hide

Synonyms of Demicheleite-(I)Hide

Other Language Names for Demicheleite-(I)Hide

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Demicheleite-(I) associated with SalammoniacNH4Cl
1 photo of Demicheleite-(I) associated with BismuthiniteBi2S3
1 photo of Demicheleite-(I) associated with Adranosite(NH4)4NaAl2(SO4)4Cl(OH)2

Related Minerals - Strunz-mindat GroupingHide

2.FC.05DjerfisheriteK6(Fe,Cu,Ni)25S26ClIso. m3m(4/m32/m) : Pm3m
2.FC.05Owensite(Ba,Pb)6(Cu,Fe,Ni)25S27Iso. m3m(4/m32/m) : Pm3m
2.FC.05ThalfenisiteTl6(Fe,Ni,Cu)25S26ClIso.
2.FC.05GmalimiteK6◻Fe2+24S27Iso. m3m(4/m32/m) : Pm3m
2.FC.05'Cu-djerfisherite'K6(Cu,Fe)25S26Cl
2.FC.05Zoharite(Ba,K)6(Fe,Cu,Ni)25S27Iso. m3m(4/m32/m) : Pm3m
2.FC.10BartoniteK6Fe20S26STet. 4/mmm(4/m2/m2/m) : I4/mmm
2.FC.10ChlorbartoniteK6Fe24S26(Cl,S)Tet. 4/mmm(4/m2/m2/m) : I4/mmm
2.FC.15dRadtkeiteHg2+3S2IClMon. 2/m : B2/m
2.FC.15aLavrentieviteHg3S2Cl2Mon.
2.FC.15aCorderoiteHg2+3S2Cl2Iso. m3(2/m3)
2.FC.15a'Arzakite'Hg2+3S2(Br,Cl)2Mon.
2.FC.15cGrechishcheviteHg2+3S2(Br,Cl,I)2Tet.
2.FC.15bKenhsuiteHg2+3S2Cl2Orth.
2.FC.20bIltisiteHgAgSClHex.
2.FC.20cPerrouditeHg5Ag4S5(I,Br)2Cl2Orth. 222 : P21212
2.FC.20aCapgaronniteAgHgClSOrth. mmm(2/m2/m2/m)
2.FC.20dHanaueriteAgHgSIOrth. mmm(2/m2/m2/m) : Pmma
2.FC.25Demicheleite-(Cl)BiSClOrth. mmm(2/m2/m2/m) : Pnma
2.FC.25Demicheleite-(Br)BiSBrOrth. mmm(2/m2/m2/m) : Pnma

Fluorescence of Demicheleite-(I)Hide

Not fluorescent

Other InformationHide

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-(I)Hide

References for Demicheleite-(I)Hide

Localities for Demicheleite-(I)Hide

Showing 4 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- 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.
Czech Republic
 
  • Moravian-Silesian Region
    • Ostrava-City District
      • Ostrava
Matýsek et al. (2022)
Matýsek et al. (2022)
Italy (TL)
 
  • Sicily
    • Metropolitan City of Messina
      • Eolie Islands (Aeolian Islands)
        • Lipari
          • Vulcano Island
Demartin et al. (2010)
Poland
 
  • Silesian Voivodeship
    • Wodzisław County
      • Rydułtowy
        • ROW Ruch Rydułtowy Mine
Patryk Kosałka
 
and/or  
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