Megakalsilite is a rare potassium aluminosilicate mineral belonging to the nepheline group. It is typically found in alkaline igneous environments as small, prismatic crystals, often closely associated with other feldspathoid minerals like kalsilite.
Is this megakalsilite?
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 megakalsilite with a known reference. Megakalsilite 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. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: anhedral grains.
Often confused with
Megakalsilite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside megakalsilite
Minerals reported to co-occur with megakalsilite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- KAlSiO₄
- Mohs hardness
- 6
- Density
- 2.58 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Hexagonal
- Crystal habit
- Anhedral grains
- Cleavage
- Distinct on {10-10}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Hyperagpaitic pegmatite. (close to kalsilite; structure)
Where rockhounds find megakalsilite
Classic worldwide localities
- Khibina alkaline massif, Kola Peninsula, Russia (type locality)
Field-hunting tip
Where it forms: Hyperagpaitic pegmatite. (close to kalsilite; structure). If you start seeing kalsilite, nepheline, leucite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify megakalsilite?+
Where is megakalsilite found?+
What rocks look like megakalsilite?+
What minerals are found with megakalsilite?+
What kind of rock does megakalsilite form in?+
What is megakalsilite used for?+
Find megakalsilite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
