Argesite is a rare bismuth halide, typically pale yellow. It is a sublimate around an active volcanic fumarole. It was first described from fumarole FA, La Fossa Crater, Vulcano, Aeolian Islands, Sicily, Italy.
Is this argesite?
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 argesite with a known reference. Argesite sits at Mohs 2.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: pale yellow.
- 5Look at form & habitCrystal system: trigonal. Typical habit: tabular crystals, crusts.
Often confused with
Argesite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside argesite
Minerals reported to co-occur with argesite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (NH₄)₇Bi₃Cl₁₆
- Mohs hardness
- 2.5
- Density
- 2.88 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Trigonal
- Crystal habit
- Tabular crystals, crusts
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A sublimate around an active volcanic fumarole
Where rockhounds find argesite
Classic worldwide localities
- Fumarole FA, Sicily, Italy
Field-hunting tip
Where it forms: A sublimate around an active volcanic fumarole. If you start seeing bismuthinite, adranosite, brontesite in float, you are in the right ground. Typical habit: tabular crystals, crusts. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify argesite?+
Where is argesite found?+
What rocks look like argesite?+
What minerals are found with argesite?+
What kind of rock does argesite form in?+
What is argesite used for?+
Find argesite on the map
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