Brindleyite is a rare nickel-rich member of the serpentine group, often appearing as small, platy, micaceous crystals. It is typically found in association with nickel deposits and is prized primarily by mineral collectors for its scarcity and specific geological occurrence.
Is this brindleyite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch brindleyite with a known reference. Brindleyite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: light green.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous to pearly.
- 4Match the color rangeCompare against the expected color range: yellow green.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: massive, platy.
Often confused with
Brindleyite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Brindleyite leaves light green, Chrysotile leaves white; luster reads vitreous to pearly on Brindleyite and silky on Chrysotile.
How to tell apart: Streak differs, so Brindleyite leaves light green, Antigorite leaves white; luster reads vitreous to pearly on Brindleyite and resinous, greasy, silky, waxy, earthy on Antigorite.
Often found alongside brindleyite
Minerals reported to co-occur with brindleyite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Ni,Al)₃(Si,Al)₂O₅(OH)₄
- Mohs hardness
- 2.5-3
- Density
- 3.17 g/cm³
- Colors
- Streak
- Light green
- Luster
- Vitreous to pearly
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Massive, platy
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As coatings on limestone and as veinlets cutting kaolinitic clays at the base of a bauxite deposit developed on karst; also a significant component of weathered ultramafic rock (Megara, Greece)
Where rockhounds find brindleyite
Classic worldwide localities
- Victorio, Grant Co., New Mexico, USA
- Marmara bauxite deposit, Megara, Greece
Field-hunting tip
Where it forms: As coatings on limestone and as veinlets cutting kaolinitic clays at the base of a bauxite deposit developed on karst; also a significant component of weathered ultramafic rock (Megara, Greece). If you start seeing bastnäsite, malachite, bayerite in float, you are in the right ground. Typical habit: massive, platy. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify brindleyite?+
Where is brindleyite found?+
Is brindleyite safe to handle?+
What rocks look like brindleyite?+
What minerals are found with brindleyite?+
What kind of rock does brindleyite form in?+
What is brindleyite used for?+
Find brindleyite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
