Mallestigite is a very rare lead sulfate-arsenate mineral typically found as small, prismatic, colorless to pale yellow crystals in oxidized lead deposits. It is best identified through its specific association with other lead-bearing minerals in its type locality in Carinthia, Austria. Due to its extreme rarity and complex composition, it is highly sought after by advanced mineral collectors.
Is this mallestigite?
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 mallestigite with a known reference. Mallestigite sits at Mohs 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: adamantine.
- 4Match the color rangeCompare against the expected color range: colorless.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: euhedral crystals.
Often confused with
Mallestigite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads adamantine on Mallestigite and resinous to subadamantine on Mimetite.
How to tell apart: Mallestigite is noticeably harder (Mohs 4 vs. 2.5-3).
How to tell apart: Luster reads adamantine on Mallestigite and resinous to subadamantine on Pyromorphite.
Often found alongside mallestigite
Minerals reported to co-occur with mallestigite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Pb₃Sb(SO₄)(AsO₄)(OH)₆·3H₂O
- Mohs hardness
- 4
- Density
- 4.91 g/cm³
- Colors
- Streak
- White
- Luster
- Adamantine
- Transparency
- Transparent to translucent
- Crystal system
- Hexagonal
- Crystal habit
- Euhedral crystals
- Cleavage
- None observed
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare secondary mineral in the oxidized zone of a hydrothermal polymetallic base-metal deposit containing galena and tetrahedrite (Austria); in weathered metallic slag (Hartz Mountains, Germany)
Where rockhounds find mallestigite
Classic worldwide localities
- Dump of a Cu-Pp-Zn mine 1 km NW of Mallestiger Mittagskogel, Finkenstein, Villach, Kärnten, Austria (type locality)
Field-hunting tip
Where it forms: A rare secondary mineral in the oxidized zone of a hydrothermal polymetallic base-metal deposit containing galena and tetrahedrite (Austria); in weathered metallic slag (Hartz Mountains, Germany). If you start seeing anglesite, brochantite, langite in float, you are in the right ground. Typical habit: euhedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify mallestigite?+
Where is mallestigite found?+
Is mallestigite safe to handle?+
What rocks look like mallestigite?+
What minerals are found with mallestigite?+
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What is mallestigite used for?+
Find mallestigite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
