Graţianite is a rare manganese-bismuth sulfosalt that typically occurs as small inclusions or anhedral grains within hydrothermal mineral assemblages. Collectors primarily seek this mineral from its type locality in Romania, where it is often associated with other base-metal sulfides in epithermal vein deposits.

Hardness

3-3.5

Mohs

Transparency

Opaque

mineralrareSulfosalt Group family

Graţianite

Hardness: 3-3.5
Transparency: Opaque

No image

Is this graţianite?

3-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 graţianite with a known reference. Graţianite sits at Mohs 3-3.5, softer than the next harder reference, harder than the previous one.
2
Match the color range
Compare against the expected color range: gray, black.
3
Look at form & habit
Crystal system: monoclinic. Typical habit: anhedral grains.

Often confused with

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

Often found alongside graţianite

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

All properties

Chemical formula: MnBi₂S₄
Mohs hardness: 3-3.5
Density: 6.031 g/cm³
Colors: Gray Black
Transparency: Opaque
Crystal system: Monoclinic
Crystal habit: Anhedral grains
Rarity: Rare
Uses: Collector
Host rock: In a geochemically complex, hydrothermal deposit of Bi-Pb-sulfosalts and Bi-chalcogenides

Where rockhounds find graţianite

Classic worldwide localities

Baia Sprie, Romania

Field-hunting tip

Where it forms: In a geochemically complex, hydrothermal deposit of Bi-Pb-sulfosalts and Bi-chalcogenides. If you start seeing cosalite, bismuthinite, chalcopyrite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify graţianite?+

Mohs hardness is 3-3.5. Common colors include gray, black.

Where is graţianite found?+

Notable localities include Baia Sprie, Romania.

Is graţianite safe to handle?+

Contains bismuth, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling and avoid creating dust.

What rocks look like graţianite?+

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

What minerals are found with graţianite?+

Graţianite commonly co-occurs with Cosalite, Bismuthinite, Chalcopyrite, Tetradymite, Gold, Sphalerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does graţianite form in?+

Where it forms: In a geochemically complex, hydrothermal deposit of Bi-Pb-sulfosalts and Bi-chalcogenides. Working float back to the host body is the standard way to chase a fresh occurrence.

What is graţianite used for?+

Graţianite is used in collector.

Find graţianite on the map

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