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.

Hardness
3.5
Mohs
Luster
Vitreous
Streak
White
Transparency
Transparent

Is this stergiouite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

  • 1
    Test the hardness
    Try to scratch stergiouite with a known reference. Stergiouite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Stergiouite leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Stergiouite typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: colorless, white.
  • 5
    Look at form & habit
    Crystal 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.

Common questions

How do you identify stergiouite?+
Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.
Where is stergiouite found?+
Notable localities include Lavrion District, Greece.
How much is stergiouite worth?+
Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.
What rocks look like stergiouite?+
Stergiouite is most often confused with Whewellite, Weddellite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with stergiouite?+
Stergiouite commonly co-occurs with Galena, Sphalerite, Smithsonite, Aurichalcite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does stergiouite form in?+
Stergiouite typically forms in slag heaps and lead-zinc hydrothermal deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is stergiouite used for?+
Stergiouite is used in collector.

Find stergiouite on the map

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