Orlandiite is a rare lead chloride selenite mineral known primarily from the Brosso mine in Italy. It typically forms as small, delicate, colorless to white tabular crystals in association with other lead minerals in oxidized hydrothermal deposits.
Is this orlandiite?
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 orlandiite with a known reference. Orlandiite sits at Mohs 2, 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 to silky.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: triclinic. Typical habit: tabular.
Often confused with
Orlandiite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads vitreous to silky on Orlandiite and adamantine, silky to pearly on Cotunnite.
How to tell apart: Laurionite is the harder of the two (Mohs 3-3.5 vs. 2); luster reads vitreous to silky on Orlandiite and adamantine, pearly on {100} on Laurionite.
Often found alongside orlandiite
Minerals reported to co-occur with orlandiite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₃Cl₄(SeO₃)·H₂O
- Mohs hardness
- 2
- Density
- 5.66 g/cm³
- Streak
- White
- Luster
- Vitreous to silky
- Transparency
- Semitransparent
- Crystal system
- Triclinic
- Crystal habit
- Tabular
- Cleavage
- Perfect on {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In the oxidized zone of a hydrothermal base-metal deposit, in a selenium-rich part
Where rockhounds find orlandiite
Classic worldwide localities
- Baccu Locci Pb–As mine, near Villaputzu, Sarrabus district, Sardinia, Italy
Field-hunting tip
Where it forms: In the oxidized zone of a hydrothermal base-metal deposit, in a selenium-rich part. If you start seeing chalcomenite, atacamite, pseudoboléite in float, you are in the right ground. Typical habit: tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify orlandiite?+
Where is orlandiite found?+
Is orlandiite safe to handle?+
What rocks look like orlandiite?+
What minerals are found with orlandiite?+
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Find orlandiite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
