Argutite is a rare germanium oxide mineral primarily found at the Tsumeb mine in Namibia. It typically occurs as small, black, sub-metallic crusts or microcrystalline aggregates associated with other germanium-bearing sulfides and oxides.
Is this argutite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch argutite with a known reference. Argutite sits at Mohs 6-7, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: black.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous to adamantine.
- 4Match the color rangeCompare against the expected color range: grayish black.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: microcrystalline aggregates.
Often confused with
Argutite vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Streak differs, so Argutite leaves black, Rutile leaves pale brown, yellowish brown; gray, greenish black with high nb–ta; luster reads vitreous to adamantine on Argutite and adamantine to submetallic on Rutile.

How to tell apart: Streak differs, so Argutite leaves black, Cassiterite leaves white, pale brown, pale gray; luster reads vitreous to adamantine on Argutite and adamantine to adamantine metallic, splendent; may be greasy on fractures on Cassiterite.
Often found alongside argutite
Minerals reported to co-occur with argutite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- GeO₂
- Mohs hardness
- 6-7
- Density
- 6.28 g/cm³
- Colors
- Streak
- Black
- Luster
- Vitreous to adamantine
- Transparency
- Semitransparent
- Crystal system
- Tetragonal
- Crystal habit
- Microcrystalline aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In a zinc deposit formed in metamorphosed lower Paleozoic sediments
Where rockhounds find argutite
Classic worldwide localities
- Argut deposit, central Pyrénées, Haute-Garonne, France
Field-hunting tip
Where it forms: In a zinc deposit formed in metamorphosed lower Paleozoic sediments. If you start seeing sphalerite, cassiterite, siderite in float, you are in the right ground. Typical habit: microcrystalline aggregates. Train your eye for that shape before scanning the outcrop.



