Oxystannomicrolite is a rare member of the pyrochlore supergroup, typically occurring as distinct, octahedral crystals in granitic pegmatites. It is often identified by its characteristic resinous luster and dense weight, usually associated with cassiterite and other rare earth minerals.

Hardness

5-5.5

Mohs

Luster

Resinous

Streak

Pale Yellow

Transparency

Translucent

mineralrarePyrochlore Supergroup family

Oxystannomicrolite

Hardness: 5-5.5
Luster: Resinous
Streak: Pale Yellow
Transparency: Translucent

No image

Is this oxystannomicrolite?

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 oxystannomicrolite with a known reference. Oxystannomicrolite sits at Mohs 5-5.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Oxystannomicrolite leaves a pale yellow streak.
3
Read the luster
Hold the specimen under a strong light. Oxystannomicrolite typically shows a resinous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, reddish-brown.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals.

Often found alongside oxystannomicrolite

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

All properties

Chemical formula: (Sn,Fe,Mn)₂(Ta,Nb)₂O₆(O,OH)
Mohs hardness: 5-5.5
Density: 6.6-7.0 g/cm³
Colors: Yellow Brown Reddish-brown
Streak: Pale Yellow
Luster: Resinous
Transparency: Translucent
Crystal system: Cubic
Crystal habit: Octahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Granite Pegmatites
Typical price: $50-300 per specimen depending on size and crystal quality

Where rockhounds find oxystannomicrolite

Classic worldwide localities

São João del Rei, Brazil
Alto Ligonha, Mozambique
Skogbøle, Finland

Field-hunting tip

Look in granite pegmatites country — that is the host setting where oxystannomicrolite typically forms. If you start seeing cassiterite, albite, columbite in float, you are in the right ground. Field specimens usually show a octahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify oxystannomicrolite?+

Mohs hardness is 5-5.5. It typically shows a resinous luster. The streak is pale yellow. Common colors include yellow, brown, reddish-brown.

Where is oxystannomicrolite found?+

Notable localities include São João del Rei, Brazil; Alto Ligonha, Mozambique; Skogbøle, Finland.

How much is oxystannomicrolite worth?+

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

Is oxystannomicrolite safe to handle?+

This mineral is radioactive. Contains minor amounts of radioactive elements like uranium or thorium; handle with care and wash hands after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What minerals are found with oxystannomicrolite?+

Oxystannomicrolite commonly co-occurs with Cassiterite, Albite, Columbite, Beryl. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does oxystannomicrolite form in?+

Oxystannomicrolite typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is oxystannomicrolite used for?+

Oxystannomicrolite is used in collector.

Find oxystannomicrolite on the map

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