Kraisslite is a rare zinc manganese magnesium hydroxide, typically deep coppery brown. It occurs in a metamorphosed stratiform zinc deposit. It was first described from Sterling Hill, Ogdensburg, Sussex Co., New Jersey, USA.
Is this kraisslite?
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 kraisslite with a known reference. Kraisslite sits at Mohs 3-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: golden brown.
- 3Read the lusterHold the specimen under a strong light. Luster: submetallic.
- 4Match the color rangeCompare against the expected color range: copper brown, dark copper brown.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: compact, foliated, scaly.
Often confused with
Kraisslite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Kraisslite leaves golden brown, Dixenite leaves brownish-red; luster reads submetallic on Kraisslite and metallic to resinous on Dixenite.
How to tell apart: Streak differs, so Kraisslite leaves golden brown, Allactite leaves gray to faint brown; luster reads submetallic on Kraisslite and vitreous, slightly greasy on fracture surfaces on Allactite.
Often found alongside kraisslite
Minerals reported to co-occur with kraisslite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Zn₃(Mn,Mg)₂₅(Fe³⁺,Al)(As³⁺O₃)₂[(Si,As⁵⁺)O₄]₁₀(OH)₁₆
- Mohs hardness
- 3-4
- Density
- 3.876 g/cm³
- Colors
- Copper brownDark copper brown
- Streak
- Golden brown
- Luster
- Submetallic
- Transparency
- Translucent
- Crystal system
- Hexagonal
- Crystal habit
- Compact, foliated, scaly
- Cleavage
- Perfect on {0001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In the zincite zone, as films and lenses in fractures, probably of secondary origin, in a metamorphosed stratiform zinc deposit
Where rockhounds find kraisslite
Classic worldwide localities
- Sterling Hill, Ogdensburg, Sussex Co., New Jersey, USA
Field-hunting tip
Where it forms: In the zincite zone, as films and lenses in fractures, probably of secondary origin, in a metamorphosed stratiform zinc deposit. If you start seeing zincite, willemite, franklinite in float, you are in the right ground. Typical habit: compact, foliated, scaly. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify kraisslite?+
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Is kraisslite safe to handle?+
What rocks look like kraisslite?+
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Find kraisslite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
