Kettnerite is a rare secondary bismuth mineral that typically occurs as small, delicate platy or tabular crystals in oxidized bismuth-bearing ore deposits. It is most frequently found as thin crusts or aggregates in association with other bismuth species and quartz, primarily in historical mining districts of Central Europe.
Is this kettnerite?
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 kettnerite with a known reference. Kettnerite sits at Mohs 3, 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: pearly.
- 4Match the color rangeCompare against the expected color range: yellow, brown, brownish yellow, yellow brown, light yellow.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: platy crystals, crusts, tabular.
Often confused with
Kettnerite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside kettnerite
Minerals reported to co-occur with kettnerite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaBi(CO₃)OF
- Mohs hardness
- 3
- Density
- 5.80 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Semitransparent
- Crystal system
- Orthorhombic
- Crystal habit
- Platy crystals, crusts, tabular
- Cleavage
- Perfect basal
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In a quartz vein cutting pegmatitic potassian feldspar (Krupka, Czech Republic)
Where rockhounds find kettnerite
Classic worldwide localities
- Bowie, Cochise Co., Arizona, USA
- Apache mine, Hidalgo Co., New Mexico, USA
- Blue Bell claims, near Baker, San Bernardino Co., California, USA
- Krupka, Krušné hory Mountains, and at Jáchymov (Joachimsthal), Czech Republic
- Niederschlema and from the Waldschacht, near Schneeberg, Saxony, and in the Clara mine, near Oberwolfach, Black Forest, Germany
- Kudul, Tajikistan
Field-hunting tip
Where it forms: In a quartz vein cutting pegmatitic potassian feldspar (Krupka, Czech Republic). If you start seeing fluorite, bismuth, bismuthinite in float, you are in the right ground. Typical habit: platy crystals, crusts, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify kettnerite?+
Where is kettnerite found?+
Is kettnerite safe to handle?+
What rocks look like kettnerite?+
What minerals are found with kettnerite?+
What kind of rock does kettnerite form in?+
What is kettnerite used for?+
Find kettnerite on the map
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