Georgiadesite is an extremely rare lead-arsenic oxychloride mineral found primarily in the historic slag heaps of Laurium, Greece. It is highly sought after by systematic mineral collectors due to its very limited locality and unusual chemistry. Specimens are typically found as tiny, clear to yellow tabular crystals growing on top of other lead-bearing minerals.
Is this georgiadesite?
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 georgiadesite with a known reference. Georgiadesite sits at Mohs 3.5, 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: resinous.
- 4Match the color rangeCompare against the expected color range: brownish yellow, white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, sometimes in aggregates.
Often confused with
Georgiadesite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside georgiadesite
Minerals reported to co-occur with georgiadesite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₄(AsO₃)Cl₄(OH)
- Mohs hardness
- 3.5
- Density
- 6.3 g/cm³
- Colors
- Streak
- White
- Luster
- Resinous
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, sometimes in aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed by the action of seawater on lead-bearing slag (Laurium, Greece)
Where rockhounds find georgiadesite
Classic worldwide localities
- Laurium, Greece, in slag
Field-hunting tip
Where it forms: Formed by the action of seawater on lead-bearing slag (Laurium, Greece). If you start seeing laurionite, fiedlerite, matlockite in float, you are in the right ground. Typical habit: tabular crystals, sometimes in aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify georgiadesite?+
Where is georgiadesite found?+
Is georgiadesite safe to handle?+
What rocks look like georgiadesite?+
What minerals are found with georgiadesite?+
What kind of rock does georgiadesite form in?+
What is georgiadesite used for?+
Find georgiadesite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
