Lintonite is a green, fibrous variety of the zeolite mineral Thomsonite-Ca. It is best known for forming attractive radiating, globular aggregates found within the cavities of amygdaloidal basalt along the North Shore of Lake Superior.

Hardness

5-5.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineraluncommonThomsonite-Ca family

Lintonite

Also: Green Thomsonite

Hardness: 5-5.5
Luster: Vitreous
Streak: White
Transparency: Translucent

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Is this lintonite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch lintonite with a known reference. Lintonite sits at Mohs 5-5.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Lintonite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Lintonite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: green, yellow-green, blue-green.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: radial fibrous, radiating spherulitic aggregates.

Often confused with

Lintonite vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside lintonite

Minerals reported to co-occur with lintonite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: NaCa₂Al₅Si₅O₂₀·6H₂O
Mohs hardness: 5-5.5
Density: 2.3-2.4 g/cm³
Colors: Green Yellow-green Blue-green
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Radial Fibrous, Radiating Spherulitic Aggregates
Cleavage: Perfect
Rarity: Uncommon
Uses: Collector, Lapidary
Host rock: Basaltic Lava Flows
Typical price: $10-50 per specimen

Where rockhounds find lintonite

2 mapped spots

Classic worldwide localities

Grand Marais, Minnesota
North Shore of Lake Superior, USA

Field-hunting tip

Look in basaltic lava flows country — that is the host setting where lintonite typically forms. If you start seeing calcite, quartz, datolite in float, you are in the right ground. Field specimens usually show a radial fibrous, radiating spherulitic aggregates habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Minnesota — start trip planning there.

Browse 2 U.S. spots for lintonite →

Common questions

How do you identify lintonite?+

Mohs hardness is 5-5.5. It typically shows a vitreous luster. The streak is white. Common colors include green, yellow-green, blue-green.

Where is lintonite found?+

Notable localities include Grand Marais, Minnesota; North Shore of Lake Superior, USA.

Can I find lintonite in the United States?+

RockHoundR maps 2 lintonite rockhounding spots across 1 U.S. states — the top states are Minnesota.

How much is lintonite worth?+

Typical asking prices fall in the range of $10-50 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like lintonite?+

Lintonite is most often confused with Prehnite, Epidote, Thomsonite-Ca. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with lintonite?+

Lintonite commonly co-occurs with Calcite, Quartz, Datolite, Laumontite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does lintonite form in?+

Lintonite typically forms in basaltic lava flows. Working float back to the host body is the standard way to chase a fresh occurrence.

What is lintonite used for?+

Lintonite is used in collector, lapidary.

Find lintonite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.