Simonkolleite is a rare secondary zinc mineral often found in the weathered slag of ancient smelting sites or oxidized ore deposits. It typically forms attractive, pearly white to colorless hexagonal plates or rosettes, making it a prized micro-mineral for collectors.
Is this simonkolleite?
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 simonkolleite with a known reference. Simonkolleite sits at Mohs 1.5, 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: colorless.
- 5Look at form & habitCrystal system: trigonal. Typical habit: hexagonal, tabular.
Often confused with
Simonkolleite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads vitreous on Simonkolleite and pearly, silky to dull or earthy in aggregates on Hydrozincite.
How to tell apart: Smithsonite is the harder of the two (Mohs 4-4.5 vs. 1.5).
How to tell apart: Hemimorphite is the harder of the two (Mohs 4.5-5 vs. 1.5).
Often found alongside simonkolleite
Minerals reported to co-occur with simonkolleite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Zn₅(OH)₈Cl₂·H₂O
- Mohs hardness
- 1.5
- Density
- 3.2 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Trigonal
- Crystal habit
- Hexagonal, tabular
- Cleavage
- {0001}, perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare secondary mineral formed by weathering of zinc-bearing slag
Where rockhounds find simonkolleite
Classic worldwide localities
- Richelsdorf foundary, Hesse, Germany (type locality)
Field-hunting tip
Where it forms: A rare secondary mineral formed by weathering of zinc-bearing slag. If you start seeing wiilfingite, hydrocerussite, diaboleite in float, you are in the right ground. Typical habit: hexagonal, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify simonkolleite?+
Where is simonkolleite found?+
Is simonkolleite safe to handle?+
What rocks look like simonkolleite?+
What minerals are found with simonkolleite?+
What kind of rock does simonkolleite form in?+
What is simonkolleite used for?+
Find simonkolleite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
