Hydroromarchite is an extremely rare tin-hydroxide mineral that typically forms as a corrosion product on ancient archaeological tin objects submerged in water. It usually appears as microscopic, pearly, white tabular crystals and is frequently associated with the anhydrous mineral romarchite. Due to its formation environment, fine specimens are highly prized by mineral collectors specializing in anthropogenic or rare secondary minerals.
Is this hydroromarchite?
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 hydroromarchite with a known reference. Hydroromarchite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Hydroromarchite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Hydroromarchite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: white, colorless.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: platy crystals, tabular.
Often confused with
Hydroromarchite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside hydroromarchite
Minerals reported to co-occur with hydroromarchite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Sn₃O₂(OH)₂
- Mohs hardness
- 2
- Density
- 4.15 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Tetragonal
- Crystal habit
- Platy Crystals, Tabular
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Corroded Tin Artifacts
- Typical price
- $50-300 per micro-mount
Where rockhounds find hydroromarchite
Classic worldwide localities
- Romarché, France
- Lake Huron, Michigan, USA
- Quebec, Canada
Field-hunting tip
Look in corroded tin artifacts country — that is the host setting where hydroromarchite typically forms. If you start seeing romarchite, cassiterite, stannite in float, you are in the right ground. Field specimens usually show a platy crystals, tabular habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydroromarchite?+
Where is hydroromarchite found?+
How much is hydroromarchite worth?+
Is hydroromarchite safe to handle?+
What rocks look like hydroromarchite?+
What minerals are found with hydroromarchite?+
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Find hydroromarchite on the map
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