Evansite is a rare hydrous aluminum phosphate mineral often found as botryoidal or stalactitic crusts. It is easily confused with opal due to its amorphous, glassy appearance, but it is typically identified by its distinctive bright green fluorescence under UV light.
Is this evansite?
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 evansite with a known reference. Evansite sits at Mohs 3.5-4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Evansite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Evansite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, bluish, greenish, yellowish.
- 5Look at form & habitCrystal system: amorphous. Typical habit: botryoidal, massive, stalactitic.
Often confused with
Evansite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside evansite
Minerals reported to co-occur with evansite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Al₃(PO₄)(OH)₆·6H₂O
- Mohs hardness
- 3.5-4
- Density
- 1.8-1.9 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Amorphous
- Crystal habit
- Botryoidal, Massive, Stalactitic
- Cleavage
- None
- Fluorescence
- Bright Green to Yellow-green Under UV
- Rarity
- Uncommon
- Uses
- Collector, Scientific Research
- Host rock
- Hydrothermal Alteration Zones in Sedimentary and Igneous Rocks
- Typical price
- $10-60 for small specimens
Where rockhounds find evansite
Classic worldwide localities
- Hungary
- Czech Republic
- United States
- Slovakia
Field-hunting tip
Look in hydrothermal alteration zones in sedimentary and igneous rocks country — that is the host setting where evansite typically forms. If you start seeing limonite, wavellite, variscite in float, you are in the right ground. Field specimens usually show a botryoidal, massive, stalactitic habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify evansite?+
Where is evansite found?+
How much is evansite worth?+
What rocks look like evansite?+
What minerals are found with evansite?+
What kind of rock does evansite form in?+
What is evansite used for?+
Find evansite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
