Hollandite is a manganese-barium oxide often found as striking metallic black prismatic crystals or radiating, needle-like sprays. It is most commonly found in oxidized manganese deposits and is often associated with other manganese oxides, requiring chemical testing for definitive identification.
Is this hollandite?
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 hollandite with a known reference. Hollandite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Hollandite leaves a black streak.
- 3Read the lusterHold the specimen under a strong light. Hollandite typically shows a metallic luster.
- 4Match the color rangeCompare against the expected color range: black, dark gray.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals, radial aggregates, fibrous masses.
Often confused with
Hollandite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Hollandite leaves black, Romanèchite leaves shiny brownish black; luster reads metallic on Hollandite and submetallic to dull on Romanèchite.
How to tell apart: Hollandite is noticeably harder (Mohs 6 vs. 4); streak differs, so Hollandite leaves black, Manganite leaves dark reddish-brown; luster reads metallic on Hollandite and submetallic on Manganite.
Often found alongside hollandite
Minerals reported to co-occur with hollandite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ba(Mn⁴⁺₆Mn³⁺₂)O₁₆
- Mohs hardness
- 6
- Density
- 4.7-5.0 g/cm³
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic Crystals, Radial Aggregates, Fibrous Masses
- Cleavage
- Good in Two Directions
- Rarity
- Uncommon
- Uses
- Collector, Ore of Manganese
- Host rock
- Hydrothermal Veins, Metamorphosed Manganese Deposits
- Typical price
- $15-150 for aesthetic specimens
Where rockhounds find hollandite
Classic worldwide localities
- India
- Germany
- USA
- Sweden
- Czech Republic
Field-hunting tip
Look in hydrothermal veins, metamorphosed manganese deposits country, the host setting where hollandite typically forms. If you start seeing braunite, hausmannite, bixbyite in float, you are in the right ground. Field specimens usually show a prismatic crystals, radial aggregates, fibrous masses habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hollandite?+
Where is hollandite found?+
How much is hollandite worth?+
What rocks look like hollandite?+
What minerals are found with hollandite?+
What kind of rock does hollandite form in?+
What is hollandite used for?+
Find hollandite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
