Bütschliite is a rare potassium calcium carbonate mineral often formed in the heat-altered zones of burning coal seams. It is typically found as small, fragile crystals associated with fairchildite and requires careful handling due to its sensitivity to humidity and moisture.
Is this bütschliite?
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 bütschliite with a known reference. Bütschliite sits at Mohs 2.5, 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: vitreous.
- 4Match the color rangeCompare against the expected color range: white.
- 5Look at form & habitCrystal system: trigonal. Typical habit: microscopic crystals.
Often confused with
Bütschliite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside bütschliite
Minerals reported to co-occur with bütschliite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- K₂Ca(CO₃)₂
- Mohs hardness
- 2.5
- Density
- 2.607 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Trigonal
- Crystal habit
- Microscopic crystals
- Cleavage
- Distinct on {0001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed in fused wood-ash clinkers in partly burned trees
Where rockhounds find bütschliite
Classic worldwide localities
- Kanabownits Canyon, Grand Canyon National Park, Coconino Co., Arizona, USA
- Kaniksu National Forest, near Coolin, Bonner Co., Idaho, USA
- Long Shop, Montgomery Co., Virginia, USA
- Eganville and Deseronto, Ontario, Canada
Field-hunting tip
Where it forms: Formed in fused wood-ash clinkers in partly burned trees. If you start seeing calcite, fairchildite in float, you are in the right ground. Typical habit: microscopic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify bütschliite?+
Where is bütschliite found?+
What rocks look like bütschliite?+
What minerals are found with bütschliite?+
What kind of rock does bütschliite form in?+
What is bütschliite used for?+
Find bütschliite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
