THE MINERAL SPANGOLITE

Chemistry: Cu₆Al(SO₄)Cl(OH)₁₂ - 3H₂O, Hydrated Copper Aluminum Sulfate Chloride Hydroxide.
Class: Sulfates.
Uses: As a minor ore of copper and as mineral specimens.
Specimens

Spangolite is a yet another classic Cornwall mineral although it was first described from a sample that came from the copper districts near Tombstone and/or Bisbee, Arizona, USA. The type locality is in doubt because the original type specimen's origin was unknown, but thought to have originated near Tombstone. Later authors have given strong evidence that the specimen is more likely from Bisbee. A good tale to tell to young collectors about keeping good records. You never know when a mineral specimen will yield a new mineral and it is a shame to have its origin in doubt! Cornwall's discovery was just a few years after the 1890 Arizona discovery.

Spangolite is a beautiful mineral. It has a blue green color that is usually quite attractive. Its aggregate crystal clusters of tabular well formed crystals are very interesting and spangolite even forms small twinned crystals that have a look similar to the head of a double bladed hatchet. Spangolite's typical tabular habit is similar to the arsenate mineral chalcophyllite.

PHYSICAL CHARACTERISTICS:

Color is blue-green; ranging from dark blue to emerald green.
Luster is vitreous.
Transparency: Specimens are transparent to translucent.
Crystal System is hexagonal; 6mm.
Crystal Habits include prismatic to tabular tapering crystals.
Cleavage is perfect in one direction (basal).
Fracture is conchoidal.
Hardness is 3
Specific Gravity is approximately 3.1 - 3.2 (average for non-metallic minerals).
Streak is light green.
Associated Minerals include azurite, cuprite, claringbullite, connellite, paratacamite, atacamite, and chyrsocolla.
Notable Occurrences include St. Day, Cornwall, England; Arenas, Sardinia; Larium, Greece; the type locality of either Tombstone or Bisbee, as well as the Copper Queen Mine and the Clifton-Morenci District of Arizona, and the Bingham and Blanchard Mine, Socorro County, New Mexico, USA.
Best Field Indicators are crystal habit, color, cleavage, associations and locality.