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.

Hardness
1-2
Mohs
Luster
Vitreous
Streak
White
Transparency
Semitransparent

Is this uricite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

  • 1
    Test the hardness
    Try to scratch uricite with a known reference. Uricite sits at Mohs 1-2, softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Streak: white.
  • 3
    Read the luster
    Hold the specimen under a strong light. Luster: vitreous.
  • 4
    Match the color range
    Compare against the expected color range: colorless, yellowish white.
  • 5
    Look at form & habit
    Crystal 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
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.

Common questions

How do you identify uricite?+
Mohs hardness is 1-2. Luster: vitreous. The streak is white. Common colors include colorless, yellowish white.
Where is uricite found?+
Notable localities include Dingo Donga Cave, near Rawlinna, Western Australia.
What rocks look like uricite?+
Uricite is most often confused with Taranakite, Brushite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with uricite?+
Uricite commonly co-occurs with Biphosphammite, Brushite, Syngenite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does uricite form in?+
Where it forms: Formed in guanos. Working float back to the host body is the standard way to chase a fresh occurrence.
What is uricite used for?+
Uricite is used in collector.

Find uricite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.

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