Mazzettiite is an extremely rare silver-mercury-lead-antimony telluride mineral found primarily in epithermal gold-silver deposits. It typically occurs as microscopic grains within complex sulfide-telluride ores and is prized by advanced mineral collectors for its unique chemistry.

Hardness

2.5-3

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Mazzettiite

Hardness: 2.5-3
Luster: Metallic
Streak: Black
Transparency: Opaque

No image

Is this mazzettiite?

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 mazzettiite with a known reference. Mazzettiite sits at Mohs 2.5-3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Mazzettiite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Mazzettiite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black, gray.
5
Look at form & habit
Crystal system: trigonal. Typical habit: fine-grained massive aggregates, microcrystalline.

Often confused with

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

Often found alongside mazzettiite

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

All properties

Chemical formula: Ag₃HgPbSbTe₅
Mohs hardness: 2.5-3
Density: 7.3-7.5 g/cm³
Colors: Black Gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Fine-grained Massive Aggregates, Microcrystalline
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Epithermal Hydrothermal Veins
Typical price: $50-500 thumbnail

Where rockhounds find mazzettiite

Classic worldwide localities

Tayoltita Mine, Durango, Mexico

Field-hunting tip

Look in epithermal hydrothermal veins country — that is the host setting where mazzettiite typically forms. If you start seeing quartz, pyrite, chalcopyrite in float, you are in the right ground. Field specimens usually show a fine-grained massive aggregates, microcrystalline habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify mazzettiite?+

Mohs hardness is 2.5-3. It typically shows a metallic luster. The streak is black. Common colors include black, gray.

Where is mazzettiite found?+

Notable localities include Tayoltita Mine, Durango, Mexico.

How much is mazzettiite 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 mazzettiite safe to handle?+

It contains toxic constituents. Contains mercury, lead, and tellurium. Should be handled with care; wash hands thoroughly after handling and avoid inhaling dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like mazzettiite?+

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

What minerals are found with mazzettiite?+

Mazzettiite commonly co-occurs with quartz, pyrite, chalcopyrite, galena, sphalerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mazzettiite form in?+

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

What is mazzettiite used for?+

Mazzettiite is used in collector.

Find mazzettiite on the map

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