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 4.5-5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Woodhouseite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Woodhouseite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, yellow, pink, brown.
- 5Look at form & habitCrystal system: trigonal. Typical habit: rhombohedral crystals.
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
- 4.5-5
- Density
- 3.37 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Rhombohedral Crystals
- Cleavage
- Poor
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Metamorphosed Aluminous Rocks and Hydrothermal Deposits
- Typical price
- $20-150 for micro-specimens
Where rockhounds find woodhouseite
Classic worldwide localities
- Champion mine, California, USA
- Dumbarton, California, USA
- Andalusite Peak, California, USA
Field-hunting tip
Look in metamorphosed aluminous rocks and hydrothermal deposits country — that is the host setting where woodhouseite typically forms. If you start seeing andalusite, pyrophyllite, quartz in float, you are in the right ground. Field specimens usually show a rhombohedral crystals habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify woodhouseite?+
Where is woodhouseite found?+
How much is woodhouseite worth?+
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.
