Tazieffite is a rare lead manganese tellurite mineral discovered in the volcanic fumaroles of the La Fossa crater on Vulcano island. It typically appears as delicate, acicular, or fibrous white to colorless crystals associated with other rare volcanic sublimate minerals.

Hardness

Mohs

Luster

Pearly

Streak

White

Transparency

Transparent

mineralrare

Tazieffite

Hardness: 2
Luster: Pearly
Streak: White
Transparency: Transparent

Is this tazieffite?

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 tazieffite with a known reference. Tazieffite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Tazieffite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Tazieffite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: acicular crystals, fibrous aggregates.

Often confused with

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

mineral

Tellurite

Mohs 2

How to tell apart: Luster reads pearly on Tazieffite and adamantine on Tellurite.

How to tell apart: Luster reads pearly on Tazieffite and adamantine on Paratellurite.

Compare →

Often found alongside tazieffite

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

All properties

Chemical formula: Pb₂₀Mn₈(TeO₃)₁₆Cl₄(OH)₁₆O₂
Mohs hardness: 2
Density: 2.79 g/cm³
Colors: White Colorless
Streak: White
Luster: Pearly
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Acicular Crystals, Fibrous Aggregates
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Fumarolic Encrustations
Typical price: $100-500 per specimen

Where rockhounds find tazieffite

Classic worldwide localities

La Fossa crater, Vulcano, Italy

Field-hunting tip

Look in fumarolic encrustations country — that is the host setting where tazieffite typically forms. If you start seeing galena, pyrite, anglesite in float, you are in the right ground. Field specimens usually show a acicular crystals, fibrous aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tazieffite?+

Mohs hardness is 2. It typically shows a pearly luster. The streak is white. Common colors include white, colorless.

Where is tazieffite found?+

Notable localities include La Fossa crater, Vulcano, Italy.

How much is tazieffite worth?+

Typical asking prices fall in the range of $100-500 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is tazieffite safe to handle?+

It contains toxic constituents. Contains lead, which is a toxic heavy metal. Always wash hands thoroughly after handling specimens and avoid inhaling any dust during collection or cleaning. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like tazieffite?+

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

What minerals are found with tazieffite?+

Tazieffite commonly co-occurs with Galena, Pyrite, Anglesite, Tellurium. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does tazieffite form in?+

Tazieffite typically forms in fumarolic encrustations. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tazieffite used for?+

Tazieffite is used in collector.

Find tazieffite on the map

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