Andreadiniite is a rare sulfosalt mineral found in hydrothermal deposits. It typically occurs as small, metallic, tabular crystals and is primarily sought after by advanced collectors focusing on rare lead-silver-copper sulfosalts.

Hardness

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrarenull family

Andreadiniite

Hardness: 3
Luster: Metallic
Streak: Black
Transparency: Opaque

No image

Is this andreadiniite?

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 andreadiniite with a known reference. Andreadiniite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Andreadiniite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Andreadiniite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black, lead-gray.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals.

Often confused with

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

mineral

Freieslebenite

Mohs 2-2.5

How to tell apart: Streak differs — Andreadiniite leaves black, Freieslebenite leaves lead-gray.

Often found alongside andreadiniite

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

All properties

Chemical formula: PbAg₃Cu₃Sb₂S₇
Mohs hardness: 3
Density: 6.63 g/cm³
Colors: Black Lead-gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Monoclinic
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins
Typical price: $50-500 thumbnail

Where rockhounds find andreadiniite

Classic worldwide localities

San Jose mine, Oruro, Bolivia

Field-hunting tip

Look in hydrothermal veins country — that is the host setting where andreadiniite typically forms. If you start seeing galena, siderite, quartz in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify andreadiniite?+

Mohs hardness is 3. It typically shows a metallic luster. The streak is black. Common colors include black, lead-gray.

Where is andreadiniite found?+

Notable localities include San Jose mine, Oruro, Bolivia.

How much is andreadiniite worth?+

Typical asking prices fall in the range of $50-500 thumbnail. Quality, size, and provenance can move individual specimens well outside that range.

Is andreadiniite safe to handle?+

It contains toxic constituents. Contains lead and silver; handle with care and wash hands thoroughly after handling. Do not ingest or inhale dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like andreadiniite?+

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

What minerals are found with andreadiniite?+

Andreadiniite commonly co-occurs with Galena, Siderite, Quartz, Pyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does andreadiniite form in?+

Andreadiniite typically forms in hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.

What is andreadiniite used for?+

Andreadiniite is used in collector.

Find andreadiniite on the map

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