Abhurite

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Abhurite
Abhurite - Shipwreck Hydra, South coast of Norway.jpg
Brownish tabular crystals of abhurite from Shipwreck "Hydra", South coast of Norway
General
Category Halide mineral
Formula
(repeating unit)
Sn21O6(OH)14Cl16
Strunz classification 3.DA.30
Crystal system Trigonal
Crystal class Trapezohedral (32)
H-M symbol: (32)
Space group R32
Unit cell a = 10.0175 Å, c = 44.014 Å; Z=3
Identification
Color Colorless
Crystal habit Platy, thin crystals, cryptocrystalline crusts
Twinning On 0001
Cleavage None
Fracture Hackly
Tenacity Fragile
Mohs scale hardness 2
Streak White
Diaphaneity Transparent
Specific gravity 4.42
Optical properties Uniaxial (+)
Refractive index nω = 2.060 nε = 2.110
Birefringence δ = 0.050
References [1][2][3]

Abhurite is a mineral of tin, oxygen, hydrogen, and chlorine with the formula Sn21O6(OH)14Cl16[3][1] or Sn3O(OH)2Cl2.[4] Its named after its type locality, a shipwreck with tin ingots at Sharm Abhur, a cove near Jeddah in the Red Sea. Abhurite forms alongside other tin minerals like romarchite and cassiterite.[5]

Locality and formation[edit]

Abhurite is attributed for forming on tin materials when in contact with sea water. The mineral was described in 1977 from a shipwreck near Hidra Island, Norway, where it occurred on pewter plates. However, that report was not recognized by the IMA, International Mineralogical Association.[1] Along with Sharm Abhur and the shipwreck near Hidra Island, abhurite was found on tin ingots in the Uluburun shipwreck. On the ingots, it was found with other tin minerals like cassiterite and romarchite, and calcium carbonate minerals like calcite and aragonite.[6]

See also[edit]

References[edit]

  1. ^ a b c Mindat.org - Abhurite
  2. ^ Webmineral.org - Abhurite
  3. ^ a b Handbook of Mineralogy - Abhurite
  4. ^ Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: "Dana's new mineralogy", p. 401. John Wiley & Sons, 1997
  5. ^ Memet, J. B. (2007). "The corrosion of metallic artefacts in seawater: descriptive analysis". In Dillmann, P.; Beranger, G.; Piccardo, P.; Matthiessen, H. Corrosion of Metallic Heritage Artefacts: Investigation, Conservation and Prediction of Long Term Behaviour. Elsevier. pp. 152–169. doi:10.1533/9781845693015.152. ISBN 9781845693015. 
  6. ^ Vandiver, Pamela B.; Goodway, Martha; Mass, Jennifer L. (2002-01-01). Materials Issues in Art and Archaeology VI: Symposium Held November 26-30, 2001, Boston, Massachusetts, U.S.A. Materials Research Society. ISBN 9781558996489.