Woodhouseite is a rare phosphate-sulfate mineral that typically occurs as small, sharp rhombohedral crystals. It is most frequently identified in high-grade metamorphic rocks rich in aluminum, such as those found in the Champion mine in California. Collectors prize it for its excellent crystal morphology and association with other rare secondary minerals.
Is this woodhouseite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch woodhouseite with a known reference. Woodhouseite sits at Mohs 4.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous, pearly on {0001}.
- 4Match the color rangeCompare against the expected color range: colorless, white, pink, pale orange.
- 5Look at form & habitCrystal system: trigonal. Typical habit: pseudo cubic, tabular.
Often confused with
Woodhouseite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside woodhouseite
Minerals reported to co-occur with woodhouseite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaAl₃(PO₄)(SO₄)(OH)₆
- Mohs hardness
- 4.5
- Density
- 3.01 g/cm³
- Streak
- White
- Luster
- Vitreous, pearly on {0001}
- Transparency
- Translucent to transparent
- Crystal system
- Trigonal
- Crystal habit
- Pseudo cubic, tabular
- Cleavage
- On {0001}, excellent
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In quartz veins in an andalusite deposit (Champion mine, California, USA)
Where rockhounds find woodhouseite
Classic worldwide localities
- Champion mine, White Mountains, Mono Co., California, USA
- Summitville district, Rio Grande Co., Colorado, USA
- Brumado, Bahia, Brazil
- La Escondida, about 150 km south-southeast of Antofagasta, Chile
- Hökensås, Västergötland, Sweden
- Iron Monarch quarry, Iron Knob, South Australia
Field-hunting tip
Where it forms: In quartz veins in an andalusite deposit (Champion mine, California, USA). If you start seeing topaz, augelite, lazulite in float, you are in the right ground. Typical habit: pseudo cubic, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify woodhouseite?+
Where is woodhouseite found?+
What rocks look like woodhouseite?+
What minerals are found with woodhouseite?+
What kind of rock does woodhouseite form in?+
What is woodhouseite used for?+
Find woodhouseite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
