Oxy-schorl is a relatively recently defined mineral species within the tourmaline supergroup, specifically recognized as the oxy-analogue of schorl. It typically appears as black, prismatic crystals that are macroscopically indistinguishable from common schorl without advanced analytical techniques. Collectors generally identify it by its specific geochemical context in evolved pegmatites and granitic environments.
Is this oxy-schorl?
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 oxy-schorl with a known reference. Oxy-schorl sits at Mohs 7 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Oxy-schorl leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Oxy-schorl typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: black, brownish-black.
- 5Look at form & habitCrystal system: trigonal. Typical habit: prismatic crystals with rounded triangular cross-sections, often striated.
Often confused with
Oxy-schorl vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside oxy-schorl
Minerals reported to co-occur with oxy-schorl. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na(Fe₂⁺₂Al)Al₆Si₆O₁₈(BO₃)₃(OH)₃O
- Mohs hardness
- 7
- Density
- 3.18-3.25 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Opaque
- Crystal system
- Trigonal
- Crystal habit
- Prismatic Crystals with Rounded Triangular Cross-sections, Often Striated
- Cleavage
- Indistinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Granite Pegmatites
- Typical price
- $20-150 for collector specimens
Where rockhounds find oxy-schorl
Classic worldwide localities
- Czech Republic
- Germany
- Italy
- Norway
Field-hunting tip
Look in granite pegmatites country — that is the host setting where oxy-schorl typically forms. If you start seeing quartz, albite, microcline in float, you are in the right ground. Field specimens usually show a prismatic crystals with rounded triangular cross-sections, often striated habit, so train your eye for that shape before scanning the outcrop.







