Bijvoetite-(Y) is an extremely rare secondary uranium carbonate mineral found primarily in the oxidation zones of uranium deposits. Collectors typically look for its distinct yellow platy crystals or crusts, which exhibit notable fluorescence under ultraviolet light.

Hardness

Mohs

Luster

Vitreous

Streak

Light yellow

Transparency

Transparent to translucent

mineralrare

Bijvoetite-(Y)

Hardness: 2
Luster: Vitreous
Streak: Light yellow
Transparency: Transparent to translucent

Is this bijvoetite-(y)?

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 bijvoetite-(y) with a known reference. Bijvoetite-(Y) sits at Mohs 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: light yellow.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: sulfur yellow.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: microscopic crystals, tabular.

Often confused with

Bijvoetite-(Y) vs. its common look-alikes, and how to tell them apart in the field.

mineral

Liebigite

Mohs 2-3

How to tell apart: Streak differs, so Bijvoetite-(Y) leaves light yellow, Liebigite leaves yellow white.

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Often found alongside bijvoetite-(y)

Minerals reported to co-occur with bijvoetite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Y₈(UO₂)₁₆O₈(CO₃)₁₆(OH)₈·39H₂O
Mohs hardness: 2
Density: 3.9 g/cm³
Colors: Sulfur yellow
Streak: Light yellow
Luster: Vitreous
Transparency: Transparent to translucent
Crystal system: Orthorhombic
Crystal habit: Microscopic crystals, tabular
Cleavage: On {001}, good
Rarity: Rare
Uses: Collector
Host rock: Very rare, in the lower portion of the oxidation zone developed above uraninite-bearing dolomitic rocks

Where rockhounds find bijvoetite-(y)

Classic worldwide localities

Shinkolobwe, Katanga Province, Congo (Shaba Province, Zaire)

Field-hunting tip

Where it forms: Very rare, in the lower portion of the oxidation zone developed above uraninite-bearing dolomitic rocks. If you start seeing lepersonnite-, sklodowskite, curite in float, you are in the right ground. Typical habit: microscopic crystals, tabular. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify bijvoetite-(y)?+

Mohs hardness is 2. Luster: vitreous. The streak is light yellow. Common colors include sulfur yellow.

Where is bijvoetite-(y) found?+

Notable localities include Shinkolobwe, Katanga Province, Congo (Shaba Province, Zaire).

Is bijvoetite-(y) safe to handle?+

Bijvoetite-(Y) contains uranium or thorium and calls for real care. This mineral is radioactive and contains uranium; handle with extreme caution, store in a lead-lined container, and wash hands thoroughly after handling. Do not inhale dust or ingest.

What rocks look like bijvoetite-(y)?+

Bijvoetite-(Y) is most often confused with Liebigite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with bijvoetite-(y)?+

Bijvoetite-(Y) commonly co-occurs with Lepersonnite-, Sklodowskite, Curite, Uranophane, Becquerelite, Rutherfordine. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does bijvoetite-(y) form in?+

Where it forms: Very rare, in the lower portion of the oxidation zone developed above uraninite-bearing dolomitic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is bijvoetite-(y) used for?+

Bijvoetite-(Y) is used in collector.

Find bijvoetite-(y) on the map

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