Uricite is a rare organic mineral that forms as an alteration product of guano in arid environments. Collectors typically find it as small, delicate, tabular crystals or fine efflorescent coatings associated with phosphate minerals.
Is this uricite?
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 uricite with a known reference. Uricite 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. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless, yellowish white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, crusts, efflorescent coatings.
Often confused with
Uricite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside uricite
Minerals reported to co-occur with uricite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- C₅H₄N₄O₃
- Mohs hardness
- 1-2
- Density
- 1.85 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, crusts, efflorescent coatings
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed in guanos
Where rockhounds find uricite
Classic worldwide localities
- Dingo Donga Cave, near Rawlinna, Western Australia
Field-hunting tip
Where it forms: Formed in guanos. If you start seeing biphosphammite, brushite, syngenite in float, you are in the right ground. Typical habit: tabular crystals, crusts, efflorescent coatings. Train your eye for that shape before scanning the outcrop.




