Arsmirandite is a rare volcanic mineral discovered in the fumaroles of the Tolbachik volcano in Russia. It typically appears as small, bright yellow to yellowish-dark grayish green to olive-greenish black platy crystals associated with other fumarolic minerals in high-temperature environments.
Is this arsmirandite?
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 arsmirandite with a known reference. Arsmirandite sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Arsmirandite leaves a grayish green with olive hue streak.
- 3Read the lusterHold the specimen under a strong light. Arsmirandite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: dark grayish green, olive-greenish black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals.
Often confused with
Arsmirandite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside arsmirandite
Minerals reported to co-occur with arsmirandite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaCu₄(AsO₄)₃
- Mohs hardness
- 2-3
- Density
- 3.71 g/cm³
- Streak
- Grayish Green with Olive Hue
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Platy Crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Fumarole Deposits
Where rockhounds find arsmirandite
Classic worldwide localities
- Tolbachik volcano, Kamchatka, Russia
Field-hunting tip
Look in fumarole deposits country, the host setting where arsmirandite typically forms. If you start seeing tenorite, hematite, sylvite in float, you are in the right ground. Field specimens usually show a platy crystals habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify arsmirandite?+
Where is arsmirandite found?+
Is arsmirandite safe to handle?+
What rocks look like arsmirandite?+
What minerals are found with arsmirandite?+
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Find arsmirandite on the map
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