Suseinargiuite is a rare sodium bismuth molybdate that forms colorless acicular crystals in hemispherical aggregates. It formed by hydrothermal and/or supergene alteration of a primary Mo-Bi mineral assemblage. Associated minerals include wulfenite, molybdenite and chalcopyrite. It was first described from Su Seinargiu, northwest of Sarroch, Cagliari, Sardinia, Italy.

Hardness

2-3

Mohs

Luster

Pearly to adamantine

Transparency

Transparent

mineralrare

Suseinargiuite

Hardness: 2-3
Luster: Pearly to adamantine
Transparency: Transparent

No image

Is this suseinargiuite?

4-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 suseinargiuite with a known reference. Suseinargiuite sits at Mohs 2-3, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Luster: pearly to adamantine.
3
Match the color range
Compare against the expected color range: colorless.
4
Look at form & habit
Crystal system: tetragonal. Typical habit: acicular crystals form hemispherical aggregates.

Often confused with

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

mineral

Thaumasite

Mohs 3.5

How to tell apart: Luster reads pearly to adamantine on Suseinargiuite and vitreous to dull, greasy, silky on Thaumasite.

How to tell apart: Luster reads pearly to adamantine on Suseinargiuite and vitreous on Ettringite.

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Often found alongside suseinargiuite

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

All properties

Chemical formula: (Na₀.₅Bi₀.₅)(MoO₄)
Mohs hardness: 2-3
Density: 5.597 g/cm³
Colors: Colorless
Luster: Pearly to adamantine
Transparency: Transparent
Crystal system: Tetragonal
Crystal habit: Acicular crystals form hemispherical aggregates
Rarity: Rare
Uses: Collector
Host rock: Formed by hydrothermal and/or supergene alteration of a primary Mo-Bi mineral assemblage

Where rockhounds find suseinargiuite

Classic worldwide localities

Su Seinargiu, northwest of Sarroch, Cagliari, Sardinia, Italy

Field-hunting tip

Where it forms: Formed by hydrothermal and/or supergene alteration of a primary Mo-Bi mineral assemblage. If you start seeing wulfenite, molybdenite, chalcopyrite in float, you are in the right ground. Typical habit: acicular crystals form hemispherical aggregates. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify suseinargiuite?+

Mohs hardness is 2-3. Luster: pearly to adamantine. Common colors include colorless.

Where is suseinargiuite found?+

Notable localities include Su Seinargiu, northwest of Sarroch, Cagliari, Sardinia, Italy.

What rocks look like suseinargiuite?+

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

What minerals are found with suseinargiuite?+

Suseinargiuite commonly co-occurs with Wulfenite, Molybdenite, Chalcopyrite, Galena, Sphalerite, Bismuthinite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does suseinargiuite form in?+

Where it forms: Formed by hydrothermal and/or supergene alteration of a primary Mo-Bi mineral assemblage. Working float back to the host body is the standard way to chase a fresh occurrence.

What is suseinargiuite used for?+

Suseinargiuite is used in collector.

Find suseinargiuite on the map

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