Stergiouite is a rare zinc oxalate mineral known primarily from the historic mining district of Lavrion, Greece. It typically forms small, colorless, glassy rhombohedral crystals found encrusting old mining slags, making it a highly sought-after species for mineral collectors specializing in rare mineralogy.
Is this stergiouite?
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 stergiouite with a known reference. Stergiouite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Stergiouite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Stergiouite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: trigonal. Typical habit: rhombohedral crystals.
Often confused with
Stergiouite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside stergiouite
Minerals reported to co-occur with stergiouite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Zn₂(H₂O)(C₂O₄)₂
- Mohs hardness
- 3.5
- Density
- 3.12 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Trigonal
- Crystal habit
- Rhombohedral Crystals
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Slag Heaps and Lead-zinc Hydrothermal Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find stergiouite
Classic worldwide localities
- Lavrion District, Greece
Field-hunting tip
Look in slag heaps and lead-zinc hydrothermal deposits country — that is the host setting where stergiouite typically forms. If you start seeing galena, sphalerite, smithsonite in float, you are in the right ground. Field specimens usually show a rhombohedral crystals habit, so train your eye for that shape before scanning the outcrop.






