Smolyaninovite is a rare secondary arsenate mineral that typically forms as bright yellow, earthy crusts in the oxidation zones of cobalt-nickel deposits. It is best identified through its association with other cobalt and nickel arsenates in hydrothermal ore veins. Due to its arsenic content and fragile nature, it is primarily a species for advanced mineralogists and specialized collections.
Is this smolyaninovite?
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 smolyaninovite with a known reference. Smolyaninovite 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. Streak: yellow.
- 3Read the lusterHold the specimen under a strong light. Luster: silky.
- 4Match the color rangeCompare against the expected color range: yellow, yellow-brown.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: massive, powdery, or as thin crusts and efflorescences.
Often confused with
Smolyaninovite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Smolyaninovite leaves yellow, Erythrite leaves pale red to pink; luster reads silky on Smolyaninovite and subadamantine, pearly on cleavages on Erythrite.
How to tell apart: Streak differs, so Smolyaninovite leaves yellow, Annabergite leaves pale green to white; luster reads silky on Smolyaninovite and subadamantine, pearly on cleavages, may be dull, earthy on Annabergite.
How to tell apart: Streak differs, so Smolyaninovite leaves yellow, Pharmacosiderite leaves yellowish green; luster reads silky on Smolyaninovite and adamantine to greasy on Pharmacosiderite.
Often found alongside smolyaninovite
Minerals reported to co-occur with smolyaninovite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Co₃Fe₂(AsO₄)₄·11H₂O
- Mohs hardness
- ~2
- Density
- 2.05-2.15 g/cm³
- Colors
- Streak
- Yellow
- Luster
- Silky
- Transparency
- Transparent
- Crystal system
- Orthorhombic
- Crystal habit
- Massive, powdery, or as thin crusts and efflorescences
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An oxidation product of Ni–Co arsenides
Where rockhounds find smolyaninovite
Classic worldwide localities
- Khovu-Aksy Ni–Co deposit, Tuva, Siberia, Russia
- Bastnäs mine, near Riddarhyttan, Västmanland, Sweden
- Bou Azzer, Morocco
- Mt. Cobalt, 110 km south of Cloncurry, Queensland, and in the Dome Rock copper mine, about 40 km northwest of Mingary, South Australia
- Sara Alicia mine, near Alamos, Sonora, Mexico
- Schneeberg, Saxony, Germany
Field-hunting tip
Where it forms: An oxidation product of Ni–Co arsenides. If you start seeing erythrite, pharmacolite, quartz in float, you are in the right ground. Typical habit: massive, powdery, or as thin crusts and efflorescences. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify smolyaninovite?+
Where is smolyaninovite found?+
Is smolyaninovite safe to handle?+
What rocks look like smolyaninovite?+
What minerals are found with smolyaninovite?+
What kind of rock does smolyaninovite form in?+
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Find smolyaninovite on the map
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