Mazzite-Mg is a rare zeolite mineral that forms distinctive hexagonal prismatic crystals in volcanic cavities. It is most frequently found lining vesicles in alkaline basalt, often occurring in complex intergrowths with other zeolite minerals.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareZeolite Group family

Mazzite-Mg

Hardness: 4
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this mazzite-mg?

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 mazzite-mg with a known reference. Mazzite-Mg sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Mazzite-Mg leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Mazzite-Mg typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: prismatic crystals, radial aggregates.

Often confused with

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

Often found alongside mazzite-mg

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

All properties

Chemical formula: (Mg,Ca,Na₂,K₂)₃(Al₆Si₁₀O₃₂)·28H₂O
Mohs hardness: 4
Density: 2.12 g/cm³
Colors: White Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Hexagonal
Crystal habit: Prismatic Crystals, Radial Aggregates
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Alkaline Basaltic Rocks
Typical price: $50-300 per specimen

Where rockhounds find mazzite-mg

Classic worldwide localities

Mont Semiol, France
Kamloops, British Columbia, Canada
Vicenza, Italy

Field-hunting tip

Look in alkaline basaltic rocks country — that is the host setting where mazzite-mg typically forms. If you start seeing phillipsite, chabazite, analcime in float, you are in the right ground. Field specimens usually show a prismatic crystals, radial aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify mazzite-mg?+

Mohs hardness is 4. It typically shows a vitreous luster. The streak is white. Common colors include white, colorless.

Where is mazzite-mg found?+

Notable localities include Mont Semiol, France; Kamloops, British Columbia, Canada; Vicenza, Italy.

How much is mazzite-mg worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like mazzite-mg?+

Mazzite-Mg is most often confused with Offretite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with mazzite-mg?+

Mazzite-Mg commonly co-occurs with Phillipsite, Chabazite, Analcime, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mazzite-mg form in?+

Mazzite-Mg typically forms in alkaline basaltic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is mazzite-mg used for?+

Mazzite-Mg is used in collector.

Find mazzite-mg on the map

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