Bertossaite is a very rare phosphate mineral belonging to the amblygonite group, typically found in highly fractionated pegmatites. It usually forms small bladed or granular clusters and is prized by advanced collectors of rare phosphate species due to its extremely limited global occurrence.

Hardness

5.5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareAmblygonite Group family

Bertossaite

Hardness: 5.5-6
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this bertossaite?

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 bertossaite with a known reference. Bertossaite sits at Mohs 5.5-6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Bertossaite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Bertossaite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, pink.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: bladed crystals, granular masses.

Often confused with

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

Often found alongside bertossaite

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

All properties

Chemical formula: Li₂(Ca,Mn,Fe²⁺)Al₄(PO₄)₄(OH,F)₄
Mohs hardness: 5.5-6
Density: 3.10 g/cm³
Colors: Colorless White Pink
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Bladed Crystals, Granular Masses
Cleavage: Good On {010}
Rarity: Rare
Uses: Collector
Host rock: Granite Pegmatites
Typical price: $50-300 per specimen

Where rockhounds find bertossaite

Classic worldwide localities

Bertossa pegmatite, Rwanda
Minas Gerais, Brazil

Field-hunting tip

Look in granite pegmatites country — that is the host setting where bertossaite typically forms. If you start seeing quartz, muscovite, beryl in float, you are in the right ground. Field specimens usually show a bladed crystals, granular masses habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify bertossaite?+

Mohs hardness is 5.5-6. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, pink.

Where is bertossaite found?+

Notable localities include Bertossa pegmatite, Rwanda; Minas Gerais, Brazil.

How much is bertossaite 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 bertossaite?+

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

What minerals are found with bertossaite?+

Bertossaite commonly co-occurs with Quartz, Muscovite, Beryl, Triplite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does bertossaite form in?+

Bertossaite typically forms in granite pegmatites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is bertossaite used for?+

Bertossaite is used in collector.

Find bertossaite on the map

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