Mroseite is a very rare tellurite mineral discovered in the oxidized zones of the Moctezuma mine in Mexico. It typically forms small, clear, tabular or platy crystals that are highly sought after by advanced collectors of rare minerals.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Mroseite

Hardness: 3.5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this mroseite?

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 mroseite with a known reference. Mroseite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Mroseite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Mroseite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, yellowish.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: platy crystals, tabular aggregates.

Often confused with

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

mineral

Tellurite

Mohs 2

How to tell apart: Mroseite is noticeably harder (Mohs 3.5 vs. 2); luster reads vitreous on Mroseite and adamantine on Tellurite.

How to tell apart: Mroseite is noticeably harder (Mohs 3.5 vs. 2); luster reads vitreous on Mroseite and adamantine on Paratellurite.

Compare →

Often found alongside mroseite

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

All properties

Chemical formula: CaTeO₃·H₂O
Mohs hardness: 3.5
Density: 4.44 g/cm³
Colors: Colorless White Yellowish
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Platy Crystals, Tabular Aggregates
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Oxidized Hydrothermal Tellurium-rich Ore Deposits
Typical price: $100-500 for small thumbnail specimens

Where rockhounds find mroseite

Classic worldwide localities

Moctezuma mine, Sonora, Mexico

Field-hunting tip

Look in oxidized hydrothermal tellurium-rich ore deposits country — that is the host setting where mroseite typically forms. If you start seeing tellurite, paratellurite, quetzalcoatlite in float, you are in the right ground. Field specimens usually show a platy crystals, tabular aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify mroseite?+

Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, yellowish.

Where is mroseite found?+

Notable localities include Moctezuma mine, Sonora, Mexico.

How much is mroseite worth?+

Typical asking prices fall in the range of $100-500 for small thumbnail specimens. Quality, size, and provenance can move individual specimens well outside that range.

Is mroseite safe to handle?+

It contains toxic constituents. Contains tellurium; avoid inhaling dust or ingesting particles during handling or lapidary work. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like mroseite?+

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

What minerals are found with mroseite?+

Mroseite commonly co-occurs with Tellurite, Paratellurite, Quetzalcoatlite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mroseite form in?+

Mroseite typically forms in oxidized hydrothermal tellurium-rich ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is mroseite used for?+

Mroseite is used in collector.

Find mroseite on the map

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