Milarite is a rare cyclosilicate mineral known for its complex hexagonal crystal structures that closely resemble beryl. Collectors typically look for it in alpine fissures or vuggy cavities within igneous rocks, where it forms distinct, glassy, transparent prisms. Because it is highly sought after by mineral enthusiasts, fine crystal specimens are considered significant cabinet pieces.
Is this milarite?
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 milarite with a known reference. Milarite sits at Mohs 5.5-6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless, white, greenish white, yellowish white.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: crystalline, granular, prismatic.
Often confused with
Milarite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside milarite
Minerals reported to co-occur with milarite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- KCa₂(Be₂AlSi₁₂O₃₀)·H₂O
- Mohs hardness
- 5.5-6
- Density
- 2.46-2.61 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent, opaque
- Crystal system
- Hexagonal
- Crystal habit
- Crystalline, granular, prismatic
- Cleavage
- Imperfect on {0001}; imperfect on {1120}
- Fluorescence
- Bluish white under SW UV
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In alpine and low-temperature hydrothermal veins; in aplites, syenites, and granite pegmatites
Where rockhounds find milarite
Classic worldwide localities
- Moat Mountain, North Conway, Carroll Co., New Hampshire, and in the Foote mine, Kings Mountain, Cleveland Co., North Carolina, USA
- Val Giuv, Tavetsch, Graubünden, Switzerland
- Habachtal, at Gasteiner, Austria
- Henneberg, Thuringia, and Tittling, Bavaria, Germany
- Cheesewring quarry, Linkinhorne, Cornwall, England
- Kent, Kazakhstan
Field-hunting tip
Where it forms: In alpine and low-temperature hydrothermal veins; in aplites, syenites, and granite pegmatites. If you start seeing orthoclase, albite, fluorite in float, you are in the right ground. Typical habit: crystalline, granular, prismatic. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify milarite?+
Where is milarite found?+
Is milarite safe to handle?+
What rocks look like milarite?+
What minerals are found with milarite?+
What kind of rock does milarite form in?+
What is milarite used for?+
Find milarite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
