Söhngeite is a rare gallium hydroxide mineral found almost exclusively in the oxidized zones of the Tsumeb Mine in Namibia. It typically occurs as small, sharp octahedral crystals or crusts associated with other secondary minerals in oxidized ore bodies.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Söhngeite

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

Is this söhngeite?

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 söhngeite with a known reference. Söhngeite 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. Söhngeite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Söhngeite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, pale yellow.
5
Look at form & habit
Crystal system: cubic. Typical habit: octahedral crystals, massive.

Often confused with

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

Often found alongside söhngeite

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

All properties

Chemical formula: Ga(OH)₃
Mohs hardness: 3.5
Density: 3.84 g/cm³
Colors: Colorless White Pale Yellow
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Cubic
Crystal habit: Octahedral Crystals, Massive
Cleavage: None
Rarity: Rare
Uses: Collector, Research
Host rock: Hydrothermal Mineral Deposits
Typical price: $50-300+ thumbnail

Where rockhounds find söhngeite

Classic worldwide localities

Tsumeb Mine, Namibia

Field-hunting tip

Look in hydrothermal mineral deposits country — that is the host setting where söhngeite typically forms. If you start seeing tsumcorite, duftite, mimetite in float, you are in the right ground. Field specimens usually show a octahedral crystals, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify söhngeite?+

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

Where is söhngeite found?+

Notable localities include Tsumeb Mine, Namibia.

How much is söhngeite worth?+

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

What rocks look like söhngeite?+

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

What minerals are found with söhngeite?+

Söhngeite commonly co-occurs with Tsumcorite, Duftite, Mimetite, Goethite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does söhngeite form in?+

Söhngeite typically forms in hydrothermal mineral deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is söhngeite used for?+

Söhngeite is used in collector, research.

Find söhngeite on the map

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