Rossite is a rare vanadium mineral that typically forms as yellow, transparent to translucent crusts or small tabular crystals in oxidized zones of uranium-vanadium deposits. It is unstable in dry air and often dehydrates to form its dimorph, metarossite. Collectors should store this mineral in a sealed container to prevent it from crumbling into a powdery form.

Hardness

2-3

Mohs

Luster

Pearly

Streak

Yellow

Transparency

Translucent

mineralrare

Rossite

Hardness: 2-3
Luster: Pearly
Streak: Yellow
Transparency: Translucent

Is this rossite?

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 rossite with a known reference. Rossite sits at Mohs 2-3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Rossite leaves a yellow streak.
3
Read the luster
Hold the specimen under a strong light. Rossite 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: triclinic. Typical habit: tabular crystals, crusts, efflorescences.

Often confused with

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

mineral

Metarossite

Mohs 2

How to tell apart: Luster reads pearly on Rossite and vitreous on Metarossite.

How to tell apart: Streak differs — Rossite leaves yellow, Sherwoodite leaves light blue; luster reads pearly on Rossite and vitreous on Sherwoodite.

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Often found alongside rossite

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

All properties

Chemical formula: CaV₂O₆·4H₂O
Mohs hardness: 2-3
Density: 2.44 g/cm³
Colors: Yellow Orange-yellow
Streak: Yellow
Luster: Pearly
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Tabular Crystals, Crusts, Efflorescences
Cleavage: Perfect in One Direction
Rarity: Rare
Uses: Collector
Host rock: Sedimentary Sandstone Formations
Typical price: $20-150 thumbnail

Where rockhounds find rossite

Classic worldwide localities

Bull Canyon, Montrose County, Colorado, USA
Paradox Valley, Colorado, USA
San Rafael Swell, Utah, USA

Field-hunting tip

Look in sedimentary sandstone formations country — that is the host setting where rossite typically forms. If you start seeing metarossite, carnotite, hewettite in float, you are in the right ground. Field specimens usually show a tabular crystals, crusts, efflorescences habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify rossite?+

Mohs hardness is 2-3. It typically shows a pearly luster. The streak is yellow. Common colors include yellow, orange-yellow.

Where is rossite found?+

Notable localities include Bull Canyon, Montrose County, Colorado, USA; Paradox Valley, Colorado, USA; San Rafael Swell, Utah, USA.

How much is rossite worth?+

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

Is rossite safe to handle?+

It contains toxic constituents. Contains vanadium, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling and avoid creating dust when cleaning specimens. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like rossite?+

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

What minerals are found with rossite?+

Rossite commonly co-occurs with Metarossite, Carnotite, Hewettite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does rossite form in?+

Rossite typically forms in sedimentary sandstone formations. Working float back to the host body is the standard way to chase a fresh occurrence.

What is rossite used for?+

Rossite is used in collector.

Find rossite on the map

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