Direnzoite is an extremely rare member of the zeolite group found in specific volcanic environments. It typically occurs as small tabular crystals associated with other zeolites and calcite in vesicle-filled cavities.

Hardness

3.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareZeolite Group family

Direnzoite

Hardness: 3.5
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this direnzoite?

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 direnzoite with a known reference. Direnzoite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Direnzoite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Direnzoite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals.

Often confused with

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

mineral

Natrolite

Mohs 5-5.5

How to tell apart: Natrolite is the harder of the two (Mohs 5-5.5 vs. 3.5).

Often found alongside direnzoite

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

All properties

Chemical formula: Na₄K₄Ca₂Si₂₀Al₈O₅₆·14H₂O
Mohs hardness: 3.5
Density: 2.16 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Volcanic Rocks
Typical price: $50-300 per specimen

Where rockhounds find direnzoite

Classic worldwide localities

Italy

Field-hunting tip

Look in volcanic rocks country, the host setting where direnzoite typically forms. If you start seeing calcite, phillipsite, chabazite in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify direnzoite?+

Mohs hardness is 3.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is direnzoite found?+

Notable localities include Italy.

How much is direnzoite 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 direnzoite?+

Direnzoite is most often confused with Natrolite, Phillipsite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with direnzoite?+

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

What kind of rock does direnzoite form in?+

Direnzoite typically forms in volcanic rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is direnzoite used for?+

Direnzoite is used in collector.

Find direnzoite on the map

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