Plumbophyllite is an exceptionally rare lead silicate mineral typically found in the oxidized zones of lead-rich hydrothermal deposits. It is most recognized for its platy, micaceous appearance that mimics other phyllosilicates but exhibits a notably higher density due to its lead content.
Is this plumbophyllite?
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 plumbophyllite with a known reference. Plumbophyllite sits at Mohs ~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.
- 4Match the color rangeCompare against the expected color range: lght blue.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: platy or micaceous aggregates.
Often confused with
Plumbophyllite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside plumbophyllite
Minerals reported to co-occur with plumbophyllite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₂Si₄O₁₀·H₂O
- Mohs hardness
- ~5
- Density
- 3.96 g/cm³
- Colors
- Lght blue
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Orthorhombic
- Crystal habit
- Platy or micaceous aggregates
- Cleavage
- Perfect on {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A tertiary mineral formed from cerussite in narrow veins in a highly siliceous hornfels in a fractured and chaotic region of limestone showing irregular skarn formation
Where rockhounds find plumbophyllite
Classic worldwide localities
- Blue Bell claims, ~11 km west of Baker, San Bernardino County, California, USA
Field-hunting tip
Where it forms: A tertiary mineral formed from cerussite in narrow veins in a highly siliceous hornfels in a fractured and chaotic region of limestone showing irregular skarn formation. If you start seeing cerussite, chrysocolla, fluorite in float, you are in the right ground. Typical habit: platy or micaceous aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify plumbophyllite?+
Where is plumbophyllite found?+
Is plumbophyllite safe to handle?+
What rocks look like plumbophyllite?+
What minerals are found with plumbophyllite?+
What kind of rock does plumbophyllite form in?+
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Find plumbophyllite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
