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.

Hardness

Mohs

Luster

Adamantine

Streak

White

Transparency

Transparent

mineralrare

Georgiadesite

Hardness: 3
Luster: Adamantine
Streak: White
Transparency: Transparent

Is this georgiadesite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch georgiadesite with a known reference. Georgiadesite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Georgiadesite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Georgiadesite typically shows a adamantine luster.
4
Match the color range
Compare against the expected color range: yellow, yellowish-white, colorless.
5
Look at form & habit
Crystal 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: Pb₁₆(AsO₃)₄Cl₁₄O(OH)₂
Mohs hardness: 3
Density: 6.05 g/cm³
Colors: Yellow Yellowish-white Colorless
Streak: White
Luster: Adamantine
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals, Sometimes in Aggregates
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Slag Dumps From Ancient Lead Mining
Typical price: $200-1000+ for rare micro specimens

Where rockhounds find georgiadesite

Classic worldwide localities

Laurium, Greece

Field-hunting tip

Look in slag dumps from ancient lead mining country — that is the host setting where georgiadesite typically forms. If you start seeing laurionite, fiedlerite, penfieldite in float, you are in the right ground. Field specimens usually show a tabular crystals, sometimes in aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify georgiadesite?+

Mohs hardness is 3. It typically shows a adamantine luster. The streak is white. Common colors include yellow, yellowish-white, colorless.

Where is georgiadesite found?+

Notable localities include Laurium, Greece.

How much is georgiadesite worth?+

Typical asking prices fall in the range of $200-1000+ for rare micro specimens. Quality, size, and provenance can move individual specimens well outside that range.

Is georgiadesite safe to handle?+

It contains toxic constituents. Contains lead and arsenic; wash hands thoroughly after handling and avoid inhaling dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like georgiadesite?+

Georgiadesite is most often confused with Laurionite, Fiedlerite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with georgiadesite?+

Georgiadesite commonly co-occurs with Laurionite, Fiedlerite, Penfieldite, Anglesite, Galena. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does georgiadesite form in?+

Georgiadesite typically forms in slag dumps from ancient lead mining. Working float back to the host body is the standard way to chase a fresh occurrence.

What is georgiadesite used for?+

Georgiadesite is used in collector.

Find georgiadesite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.