Hydrohonessite is a rare nickel-iron sulfate hydroxide mineral typically found as a secondary weathering product in nickel-sulfide ore deposits. It usually appears as fine-grained, yellow, platy crusts or coatings and is structurally related to the pyroaurite-sjögrenite group.
Is this hydrohonessite?
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 hydrohonessite with a known reference. Hydrohonessite sits at Mohs 1-2 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Hydrohonessite leaves a yellow streak.
- 3Read the lusterHold the specimen under a strong light. Hydrohonessite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: yellow, yellowish-green.
- 5Look at form & habitCrystal system: trigonal. Typical habit: platy crystals, crusts, coatings.
Often confused with
Hydrohonessite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside hydrohonessite
Minerals reported to co-occur with hydrohonessite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ni₆Fe³⁺₂SO₄(OH)₁₆·7H₂O
- Mohs hardness
- 1-2
- Density
- 2.16 g/cm³
- Colors
- Streak
- Yellow
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Platy Crystals, Crusts, Coatings
- Cleavage
- Perfect Basal
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Nickel-sulfide Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find hydrohonessite
Classic worldwide localities
- Agnew mine, Western Australia
- Woodsreef mine, New South Wales, Australia
Field-hunting tip
Look in nickel-sulfide deposits country — that is the host setting where hydrohonessite typically forms. If you start seeing honessite, morenosite, nickel-hexahydrite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts, coatings habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hydrohonessite?+
Where is hydrohonessite found?+
How much is hydrohonessite worth?+
Is hydrohonessite safe to handle?+
What rocks look like hydrohonessite?+
What minerals are found with hydrohonessite?+
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Find hydrohonessite on the map
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