Hydroxylpyromorphite is a rare member of the apatite supergroup characterized by its hydroxyl-dominant structure compared to its more common phosphate counterparts. Collectors should look for its distinctive resinous luster and hexagonal crystal habit, often found as secondary minerals in the oxidized zones of lead-rich ore bodies.
Is this hydroxylpyromorphite?
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 hydroxylpyromorphite with a known reference. Hydroxylpyromorphite sits at Mohs 3.5-4, 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.
- 4Match the color rangeCompare against the expected color range: grayish white.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: hexagonal prisms, barrel-shaped crystals, crusts, globular.
Often confused with
Hydroxylpyromorphite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads vitreous on Hydroxylpyromorphite and resinous to subadamantine on Pyromorphite.
How to tell apart: Luster reads vitreous on Hydroxylpyromorphite and resinous to subadamantine on Mimetite.
How to tell apart: Luster reads vitreous on Hydroxylpyromorphite and subresinous to subadamantine on Vanadinite.
Often found alongside hydroxylpyromorphite
Minerals reported to co-occur with hydroxylpyromorphite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₅(PO₄)₃(OH)
- Mohs hardness
- 3.5-4
- Density
- 7.32 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Hexagonal
- Crystal habit
- Hexagonal prisms, barrel-shaped crystals, crusts, globular
- Cleavage
- Indistinct on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A geogenic secondary lead phase and not post-mining in origin
Where rockhounds find hydroxylpyromorphite
Classic worldwide localities
- Copps mine, Gogebic County, Michigan, USA
Field-hunting tip
Where it forms: A geogenic secondary lead phase and not post-mining in origin. If you start seeing quartz in float, you are in the right ground. Typical habit: hexagonal prisms, barrel-shaped crystals, crusts, globular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydroxylpyromorphite?+
Where is hydroxylpyromorphite found?+
Is hydroxylpyromorphite safe to handle?+
What rocks look like hydroxylpyromorphite?+
What minerals are found with hydroxylpyromorphite?+
What kind of rock does hydroxylpyromorphite form in?+
What is hydroxylpyromorphite used for?+
Find hydroxylpyromorphite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
