Ruitenbergite is a rare calcium borate mineral known primarily from salt mine localities in New Brunswick, Canada. It typically forms as delicate, transparent to white bladed or tabular crystals within evaporite sequences.
Is this ruitenbergite?
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 ruitenbergite with a known reference. Ruitenbergite sits at Mohs 3 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Ruitenbergite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Ruitenbergite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: bladed to tabular crystals.
Often confused with
Ruitenbergite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside ruitenbergite
Minerals reported to co-occur with ruitenbergite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₄B₁₈O₃₀(OH)₆·13H₂O
- Mohs hardness
- 3
- Density
- 2.12 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Bladed to Tabular Crystals
- Cleavage
- Perfect On {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Evaporite Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find ruitenbergite
Classic worldwide localities
- Penobsquis, New Brunswick, Canada
Field-hunting tip
Look in evaporite deposits country — that is the host setting where ruitenbergite typically forms. If you start seeing halite, sylvite, glauberite in float, you are in the right ground. Field specimens usually show a bladed to tabular crystals habit, so train your eye for that shape before scanning the outcrop.






