Lemoynite is a rare silicate mineral primarily known from alkaline pegmatites and intrusive complexes. Collectors should look for delicate, radiating sprays or acicular clusters of white-to-colorless crystals perched on matrix with minerals like aegirine or serandite.
Is this lemoynite?
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 lemoynite with a known reference. Lemoynite sits at Mohs 4, 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: yellowish white, light blue.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: bladed, prismatic, wheat sheaf.
Often confused with
Lemoynite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Eudialyte is the harder of the two (Mohs 5-6 vs. 4).
How to tell apart: Zircon is the harder of the two (Mohs 7.5 vs. 4).
How to tell apart: Analcime is the harder of the two (Mohs 5-5.5 vs. 4).
Often found alongside lemoynite
Minerals reported to co-occur with lemoynite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂CaZr₂Si₁₀O₂₆(H₂O)₆
- Mohs hardness
- 4
- Density
- 2.29 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to opaque
- Crystal system
- Monoclinic
- Crystal habit
- Bladed, prismatic, wheat sheaf
- Cleavage
- Perfect on {100} and {010}; imperfect or parting on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An uncommon mineral, in pegmatite in an intrusive alkalic gabbro-syenite complex (Mpnt Saint-Hilaire, Canada); in miarolytic cavities in a nepheline syenite sill (near Saint-Amable, Canada)
Where rockhounds find lemoynite
Classic worldwide localities
- Mont Saint-Hilaire and near Saint-Amable, Quebec, Canada
Field-hunting tip
Where it forms: An uncommon mineral, in pegmatite in an intrusive alkalic gabbro-syenite complex (Mpnt Saint-Hilaire, Canada); in miarolytic cavities in a nepheline syenite sill (near Saint-Amable, Canada). If you start seeing sodalite, nepheline, eudialyte in float, you are in the right ground. Typical habit: bladed, prismatic, wheat sheaf. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify lemoynite?+
Where is lemoynite found?+
What rocks look like lemoynite?+
What minerals are found with lemoynite?+
What kind of rock does lemoynite form in?+
What is lemoynite used for?+
Find lemoynite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
