Silinaite is a rare phyllosilicate mineral that typically forms as white, platy crystals in alkaline igneous complexes. It is most famously found in the miarolitic cavities of Mont Saint-Hilaire, where it occurs alongside a variety of exotic rare-earth minerals. Due to its softness and perfect cleavage, specimens should be handled with care to prevent damage.
Is this silinaite?
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 silinaite with a known reference. Silinaite sits at Mohs 2.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Silinaite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Silinaite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: white, colorless.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals.
Often confused with
Silinaite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Steacyite is the harder of the two (Mohs 5 vs. 2.5); luster reads pearly on Silinaite and vitreous on Steacyite.
How to tell apart: Gonnardite is the harder of the two (Mohs 5 vs. 2.5); luster reads pearly on Silinaite and vitreous on Gonnardite.
Often found alongside silinaite
Minerals reported to co-occur with silinaite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaLiSi₂O₅·2H₂O
- Mohs hardness
- 2.5
- Density
- 2.32 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Platy Crystals
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Alkaline Igneous Intrusions
- Typical price
- $50-300 per specimen
Where rockhounds find silinaite
Classic worldwide localities
- Poudrette Quarry, Mont Saint-Hilaire, Quebec, Canada
Field-hunting tip
Look in alkaline igneous intrusions country, the host setting where silinaite typically forms. If you start seeing microcline, aegirine, analcime in float, you are in the right ground. Field specimens usually show a platy crystals habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify silinaite?+
Where is silinaite found?+
How much is silinaite worth?+
What rocks look like silinaite?+
What minerals are found with silinaite?+
What kind of rock does silinaite form in?+
What is silinaite used for?+
Find silinaite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
