THE MINERAL WOODHOUSEITE

  • Chemistry: CaAl3PO4SO4(OH)6, Calcium Aluminum Phosphate Sulfate Hydroxide.
  • Class: Sulfates; although sometimes classified as a Phosphate.
  • Group: Beudantite
  • Uses: Only as mineral specimens.
  • Specimens

Woodhouseite is a rare mineral that is almost exclusively from a single location at Champion Andalusite Mine on the western slopes of the White Mountain Peak in Mono County, California. It forms flesh-colored to colorless pseudocubic rhombohedrons. The crystals can look nearly cubic, but the angles between the faces are not exactly 90 degrees as is required for a true cube. Wedge-shaped crystals and distorted and modified rhombohedrons are also seen. Faces tend to be curved and striated. It forms in quartz veins with topaz, tourmaline, andalusite and svanbergite, another rare phosphate-sulfate mineral.

Woodhouseite is a difficult mineral to classify in that it has both a phosphate anion group and a sulfate anion group. The phosphate anion group would normally dictate that woodhouseite be classified in the Phosphate Class of minerals. But woodhouseite's sulfate anion is intricate and essential in its structure, while the phosphate anions can be substituted for to at least a limited degree. Some other classification schemes may place woodhouseite in the Phosphate Class however.

PHYSICAL CHARACTERISTICS:

  • Color is flesh-colored, pink, pale orange to colorless.
  • Luster is vitreous.
  • Transparency: Specimens are mostly translucent to small crystals being transparent.
  • Crystal System is trigonal.
  • Crystal Habits include pseudocubic rhombohedrons and wedge-shaped crystals. Distorted and modified rhombohedrons are also seen. Faces tend to be curved and striated.
  • Cleavage is perfect in one direction (basal).
  • Hardness is 4.5
  • Specific Gravity is approximately 3.0 (average for non-metallic minerals).
  • Streak is white.
  • Associated Minerals include quartz, topaz, tourmaline, andalusite and svanbergite.
  • Notable Occurrence is limited to the Champion Andalusite Mine on the western slopes of the White Mountain Peak in Mono County, California, USA.
  • Best Field Indicators are crystal habit, striations, color and locality.
WOODHOUSEITE specimens:
(hover for more info)
WOODHOUSEITE specimen wod-1
$ 45.00
Dims:0.8x0.5x0.3" (2.0x1.3x0.8 cm)
Wt: 0.07oz. (1.9g)
White Mountain Mine, Mono cty., California
This thumbnail specimen consists of a layer of yellowish woodhouseite crystals growing on a terminated quartz crystal. These crystals are tiny, but with the aid of a loupe, one can distinguish the pseudocubic habit that this mineral typically shows. The true symmetry of these crystals is hexagonal. Also evident is the vitreous luster of this mineral. This specimen shows no damage; it is a good example of this rare species.
no photo
wod-1 ($ 45.00)
White Mountain Mine, Mono cty., California
WOODHOUSEITE specimen wod-2
$ 30.00
Dims:2.2x1.5x0.9" (5.6x3.8x2.3 cm)
Wt: 1.7oz. (49g)
Champion Mine, Mono cty., California
This specimen consists of a cluster of quartz crystals coated with a honey-colored dusting of woodhouseite crystals. Overall, the woodhouseite crystals are too small to distinguish the hexagonal form of this mineral. The only damage to this specimen is on the edges of the quartz cluster.
no photo
wod-2 ($ 30.00)
Champion Mine, Mono cty., California

 


Copyright ©1995-2023 by Amethyst Galleries, Inc.