Mawbyite is a rare secondary mineral typically found in the oxidized zones of base metal deposits. It is best identified by its distinct brownish-red, platy, or tabular crystals that often form crusts associated with other lead-bearing minerals. Its primary occurrence is the world-famous Tsumeb mine in Namibia.
Is this mawbyite?
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 mawbyite with a known reference. Mawbyite 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: yellow-orange.
- 3Read the lusterHold the specimen under a strong light. Luster: adamantine.
- 4Match the color rangeCompare against the expected color range: light brown, reddish brown, pale orange, orange brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: spherical, wheat sheaf.
Often confused with
Mawbyite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Mawbyite leaves yellow-orange, Carminite leaves reddish yellow; luster reads adamantine on Mawbyite and vitreous, pearly on cleavages on Carminite.
How to tell apart: Streak differs, so Mawbyite leaves yellow-orange, Arseniosiderite leaves ocher-yellow; luster reads adamantine on Mawbyite and submetallic to silky on Arseniosiderite.
Often found alongside mawbyite
Minerals reported to co-occur with mawbyite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- PbFe₂ (AsO₄)₂(OH)₂
- Mohs hardness
- ~4
- Density
- 5.5 g/cm³
- Colors
- Streak
- Yellow-orange
- Luster
- Adamantine
- Transparency
- Transparent to translucent
- Crystal system
- Monoclinic
- Crystal habit
- Spherical, wheat sheaf
- Cleavage
- On {001}, good
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In an arsenic-rich reaction halo in fractures and cavities in a spessartine-quartz rock in the oxidization zone of a metamorphosed stratiform Pb–Zn orebody (Broken Hill, Australia)
Where rockhounds find mawbyite
Classic worldwide localities
- Kintore open cut, Broken Hill, New South Wales, Australia
- Moldava, 20 km northwest of Teplice, Czech Republic
- Clara mine, near Oberwolfach, the Silberbrünnle mine, near Gengenbach, and in the St. Josef mine, Schuttertal, Black Forest, Germany
- Oberwiesenthal, Saxony, Germany
Field-hunting tip
Where it forms: In an arsenic-rich reaction halo in fractures and cavities in a spessartine-quartz rock in the oxidization zone of a metamorphosed stratiform Pb–Zn orebody (Broken Hill, Australia). If you start seeing corkite–beudantite, adamite–olivenite, duftite in float, you are in the right ground. Typical habit: spherical, wheat sheaf. Train your eye for that shape before scanning the outcrop.
Common questions
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Find mawbyite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
