Zippeite is a secondary uranium sulfate mineral that typically forms as bright yellow to orange crusts or delicate acicular sprays in the oxidized zones of uranium mines. Collectors value it for its vivid fluorescence under long-wave ultraviolet light, but it requires careful handling due to its radioactivity.

Hardness

Mohs

Luster

Pearly

Streak

Yellow

Transparency

Translucent

mineraluncommon

Zippeite

Hardness: 2
Luster: Pearly
Streak: Yellow
Transparency: Translucent

Is this zippeite?

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 zippeite with a known reference. Zippeite 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. Zippeite leaves a yellow streak.
3
Read the luster
Hold the specimen under a strong light. Zippeite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: orange, yellow, orange-yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: crusts, acicular sprays, radiating tufts.

Often confused with

Zippeite vs. its common look-alikes — and how to tell them apart in the field.

mineral

Johannite

Mohs 2

How to tell apart: Streak differs — Zippeite leaves yellow, Johannite leaves pale green; luster reads pearly on Zippeite and vitreous on Johannite.

How to tell apart: Streak differs — Zippeite leaves yellow, Uranopilite leaves pale yellow.

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Often found alongside zippeite

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

All properties

Chemical formula: K₄(UO₂)₆(SO₄)₃(OH)₁₀·4H₂O
Mohs hardness: 2
Density: 3.6 g/cm³
Colors: Orange Yellow Orange-yellow
Streak: Yellow
Luster: Pearly
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Crusts, Acicular Sprays, Radiating Tufts
Cleavage: Perfect
Fluorescence: Bright Yellow-green Under UV
Rarity: Uncommon
Uses: Collector
Host rock: Oxidized Zones of Uranium-bearing Deposits
Typical price: $20-150 for thumbnail to small cabinet specimens

Where rockhounds find zippeite

Classic worldwide localities

Jachymov (Czech Republic)
Utah (USA)
Colorado (USA)
Saxony (Germany)

Field-hunting tip

Look in oxidized zones of uranium-bearing deposits country — that is the host setting where zippeite typically forms. If you start seeing uraninite, gypsum, johannite in float, you are in the right ground. Field specimens usually show a crusts, acicular sprays, radiating tufts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify zippeite?+

Mohs hardness is 2. It typically shows a pearly luster. The streak is yellow. Common colors include orange, yellow, orange-yellow.

Where is zippeite found?+

Notable localities include Jachymov (Czech Republic); Utah (USA); Colorado (USA); Saxony (Germany).

How much is zippeite worth?+

Typical asking prices fall in the range of $20-150 for thumbnail to small cabinet specimens. Quality, size, and provenance can move individual specimens well outside that range.

Is zippeite safe to handle?+

This mineral is radioactive. It contains toxic constituents. This mineral is radioactive and contains uranium. Handle with caution, use gloves, avoid inhalation of dust, and store in a shielded container away from living spaces. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like zippeite?+

Zippeite is most often confused with Johannite, Uranopilite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with zippeite?+

Zippeite commonly co-occurs with Uraninite, Gypsum, Johannite, Uranopilite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does zippeite form in?+

Zippeite typically forms in oxidized zones of uranium-bearing deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is zippeite used for?+

Zippeite is used in collector.

Find zippeite on the map

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