Ammoniozippeite is a rare secondary uranium sulfate mineral typically found as yellow-orange crusts or small platy crystals in oxidized uranium-bearing ore deposits. Due to its radioactive nature, it is primarily sought after by advanced mineral collectors who specialize in uranium minerals.

Hardness

Mohs

Luster

Pearly

Streak

Yellow

Transparency

Translucent

mineralrareZippeite Group family

Ammoniozippeite

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

Is this ammoniozippeite?

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 ammoniozippeite with a known reference. Ammoniozippeite 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. Ammoniozippeite leaves a yellow streak.
3
Read the luster
Hold the specimen under a strong light. Ammoniozippeite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: yellow, orange-yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: platy crystals, crusts, aggregates.

Often confused with

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

Often found alongside ammoniozippeite

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

All properties

Chemical formula: (NH₄)₂(UO₂)₄(SO₄)₂(OH)₆·3H₂O
Mohs hardness: 2
Density: 3.9 g/cm³
Colors: Yellow Orange-yellow
Streak: Yellow
Luster: Pearly
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Platy Crystals, Crusts, Aggregates
Cleavage: Perfect On {001}
Fluorescence: Bright Yellow-green Under UV
Rarity: Rare
Uses: Collector
Host rock: Oxidized Uranium Deposits
Typical price: $50-300 per specimen

Where rockhounds find ammoniozippeite

Classic worldwide localities

Utah (USA)
Colorado (USA)
Czech Republic

Field-hunting tip

Look in oxidized uranium deposits country, the host setting where ammoniozippeite typically forms. If you start seeing gypsum, schroeckingerite, uraninite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts, aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ammoniozippeite?+

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

Where is ammoniozippeite found?+

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

How much is ammoniozippeite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is ammoniozippeite safe to handle?+

This mineral is radioactive. It contains toxic constituents. Radioactive material; store in a shielded container and avoid inhalation or ingestion of dust. Handle with gloves and wash hands thoroughly after contact. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like ammoniozippeite?+

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

What minerals are found with ammoniozippeite?+

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

What kind of rock does ammoniozippeite form in?+

Ammoniozippeite typically forms in oxidized uranium deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ammoniozippeite used for?+

Ammoniozippeite is used in collector.

Find ammoniozippeite on the map

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