Parabrandtite is a rare manganese arsenate mineral found primarily in the unique deposit at the Sterling Hill Mine. It typically forms colorless to white, thin bladed crystals and is visually difficult to distinguish from its polymorph, Brandtite, without laboratory analysis.

Hardness

3-4

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareFairfieldite Group family

Parabrandtite

Hardness: 3-4
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this parabrandtite?

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 parabrandtite with a known reference. Parabrandtite sits at Mohs 3-4, 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: colorless.
5
Look at form & habit
Crystal system: triclinic. Typical habit: aggregates.

Often confused with

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

mineral

Fairfieldite

Mohs 3.5

How to tell apart: Luster reads vitreous on Parabrandtite and pearly to subadamantine, vitreous on the {001} cleavage on Fairfieldite.

Often found alongside parabrandtite

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

All properties

Chemical formula: Ca₂Mn(AsO₄)₂·2H₂O
Mohs hardness: 3-4
Density: 3.55 g/cm³
Colors: Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Triclinic
Crystal habit: Aggregates
Cleavage: On {010} and {110}, perfect
Rarity: Rare
Uses: Collector
Host rock: Very rare, in a vein in primary ore from a metamorphosed stratiform zinc orebody

Where rockhounds find parabrandtite

Classic worldwide localities

Sterling Hill, Ogdensburg, Sussex Co., New Jersey, USA

Field-hunting tip

Where it forms: Very rare, in a vein in primary ore from a metamorphosed stratiform zinc orebody. If you start seeing sarkinite, franklinite, willemite in float, you are in the right ground. Typical habit: aggregates. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify parabrandtite?+

Mohs hardness is 3-4. Luster: vitreous. The streak is white. Common colors include colorless.

Where is parabrandtite found?+

Notable localities include Sterling Hill, Ogdensburg, Sussex Co., New Jersey, USA.

Is parabrandtite safe to handle?+

Parabrandtite contains arsenic and calls for real care. Contains arsenic, a toxic heavy metal; handle with care, avoid creating dust, and wash hands thoroughly after handling.

What rocks look like parabrandtite?+

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

What minerals are found with parabrandtite?+

Parabrandtite commonly co-occurs with Sarkinite, Franklinite, Willemite, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does parabrandtite form in?+

Where it forms: Very rare, in a vein in primary ore from a metamorphosed stratiform zinc orebody. Working float back to the host body is the standard way to chase a fresh occurrence.

What is parabrandtite used for?+

Parabrandtite is used in collector.

Find parabrandtite on the map

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