Cerchiaraite-(Al) is a rare silicate mineral primarily found in the manganese-rich deposits of the Cerchiara mine in Italy. It typically occurs as small, pale yellow to brown tabular crystals, often forming in association with manganese minerals like braunite within metasedimentary host rocks.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Cerchiaraite-(Al)

Hardness: 4
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this cerchiaraite-(al)?

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 cerchiaraite-(al) with a known reference. Cerchiaraite-(Al) sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Cerchiaraite-(Al) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Cerchiaraite-(Al) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, colorless.
5
Look at form & habit
Crystal system: tetragonal. Typical habit: tabular crystals, subhedral grains.

Often confused with

Cerchiaraite-(Al) vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside cerchiaraite-(al)

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

All properties

Chemical formula: Ba₄Mn³⁺Al₃Si₆O₂₀(OH)₃Cl
Mohs hardness: 4
Density: 3.31 g/cm³
Colors: Yellow Brown Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Tetragonal
Crystal habit: Tabular Crystals, Subhedral Grains
Cleavage: Distinct On {001}
Rarity: Rare
Uses: Collector
Host rock: Manganese-rich Chert Layers in Metasedimentary Rocks
Typical price: $50-300 per specimen

Where rockhounds find cerchiaraite-(al)

Classic worldwide localities

Cerchiara Mine, Borghetto di Vara, Italy
Val di Vara, Liguria, Italy

Field-hunting tip

Look in manganese-rich chert layers in metasedimentary rocks country — that is the host setting where cerchiaraite-(al) typically forms. If you start seeing quartz, barite, braunite in float, you are in the right ground. Field specimens usually show a tabular crystals, subhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cerchiaraite-(al)?+

Mohs hardness is 4. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, colorless.

Where is cerchiaraite-(al) found?+

Notable localities include Cerchiara Mine, Borghetto di Vara, Italy; Val di Vara, Liguria, Italy.

How much is cerchiaraite-(al) worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like cerchiaraite-(al)?+

Cerchiaraite-(Al) is most often confused with Cerchiaraite-(Fe). A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with cerchiaraite-(al)?+

Cerchiaraite-(Al) commonly co-occurs with Quartz, Barite, Braunite, Todorokite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does cerchiaraite-(al) form in?+

Cerchiaraite-(Al) typically forms in manganese-rich chert layers in metasedimentary rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is cerchiaraite-(al) used for?+

Cerchiaraite-(Al) is used in collector.

Find cerchiaraite-(al) on the map

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