Ferrolaueite is a rare phosphate mineral that occurs as a secondary alteration product in complex granite pegmatites. It is typically identified as small, brownish tabular crystals closely associated with other phosphate minerals, often requiring X-ray diffraction or chemical analysis for definitive field identification.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareLaueite Group family

Ferrolaueite

Hardness: 3
Luster: Vitreous
Streak: White
Transparency: Translucent

No image

Is this ferrolaueite?

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 ferrolaueite with a known reference. Ferrolaueite 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. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: brownish yellow, light yellow.
5
Look at form & habit
Crystal system: triclinic. Typical habit: tabular crystals.

Often confused with

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

Often found alongside ferrolaueite

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

All properties

Chemical formula: FeFe₂(PO₄)₂(OH)₂·8H₂O
Mohs hardness: 3
Density: 2.75 g/cm³
Colors: Brownish yellow Light yellow
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Tabular crystals
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Probably considerd to be ferroan laueite and not s separate species

Where rockhounds find ferrolaueite

Classic worldwide localities

Hagendorf-Pleystein Pegmatite (Germany)
Tip Top Mine (USA)

Field-hunting tip

Where it forms: Probably considerd to be ferroan laueite and not s separate species. If you start seeing triphylite, sicklerite, phosphosiderite in float, you are in the right ground. Typical habit: tabular crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify ferrolaueite?+

Mohs hardness is 3. Luster: vitreous. The streak is white. Common colors include brownish yellow, light yellow.

Where is ferrolaueite found?+

Notable localities include Hagendorf-Pleystein Pegmatite (Germany); Tip Top Mine (USA).

What rocks look like ferrolaueite?+

Ferrolaueite is most often confused with Laueite, Stewartite, Pseudolaueite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with ferrolaueite?+

Ferrolaueite commonly co-occurs with Triphylite, Sicklerite, Phosphosiderite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ferrolaueite form in?+

Where it forms: Probably considerd to be ferroan laueite and not s separate species. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ferrolaueite used for?+

Ferrolaueite is used in collector.

Find ferrolaueite on the map

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