ABHURITE

Composition: Sn₂O(OH)₂Cl₂
  

Crystal System: Trigonal Rhombohedral.
Hardness: 2.
Specific Gravity: 4.42.
Colour: Colourless to creamish.
Lustre: Opalescent.
Streak: White.
Fracture: Uneven.
Cleavage: None.

Localities:
    Wreck site of the SS Cheerful, 18 miles NNW of St. Ives, Cornwall. (First British Occurrence).
    Unnamed Wreck, Off Bigbury Bay, South Hams, Devon. (Tin oxy-chloride.)
    Wreck site of the SS Liverpool, Of Anglesey, Wales.  (On refined Cornish tin).
Reference:  
    B. Gamble specimen. X-rd by Dr. D. Green, Manchester  University Museum. No. Manch. XRD 196. April 1995.
Additional Notes. 
    See Rev. Wm. Gregor. (1818) Observations on a remarkable change which Metallic Tin undergoes, under peculiar circumstances, and on its partial conversion to a Muriate of Tin. Transactions of the Royal Geological Society of Cornwall. Vol. 1. pp51 - 59. If the material described in this article was abhurite then it predates the discovery at the type locality.  It is also unusual in that it was found on land. All previous discoveries of abhurite have been at sea on various wrecks.

    In Britain abhurite has also been recorded from the wreck of the SS Liverpool, Near Anglesey, Wales. It was on refined Cornish tin.
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