Nekoite is a rare calcium silicate mineral typically found in cavities within contact-metamorphosed limestone. Collectors look for its delicate, white, bladed or fibrous crystal clusters that often form radiating spray habits.

Hardness

4.5

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrareTobermorite Group family

Nekoite

Hardness: 4.5
Luster: Pearly
Streak: White
Transparency: Translucent

Is this nekoite?

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 nekoite with a known reference. Nekoite sits at Mohs 4.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Nekoite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Nekoite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: white, colorless.
5
Look at form & habit
Crystal system: triclinic. Typical habit: bladed crystals, radial aggregates, fibrous.

Often confused with

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

How to tell apart: Nekoite is noticeably harder (Mohs 4.5 vs. 2.5).

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Often found alongside nekoite

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

All properties

Chemical formula: Ca₃Si₆O₁₅·7H₂O
Mohs hardness: 4.5
Density: 2.26 g/cm³
Colors: White Colorless
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Triclinic
Crystal habit: Bladed Crystals, Radial Aggregates, Fibrous
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Metamorphosed Limestone
Typical price: $20-150 per specimen depending on size and quality

Where rockhounds find nekoite

Classic worldwide localities

Goodsprings, Nevada, USA
Santa Monica Mountains, California, USA
Crestmore, California, USA

Field-hunting tip

Look in metamorphosed limestone country, the host setting where nekoite typically forms. If you start seeing apophyllite, calcite, prehnite in float, you are in the right ground. Field specimens usually show a bladed crystals, radial aggregates, fibrous habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nekoite?+

Mohs hardness is 4.5. It typically shows a pearly luster. The streak is white. Common colors include white, colorless.

Where is nekoite found?+

Notable localities include Goodsprings, Nevada, USA; Santa Monica Mountains, California, USA; Crestmore, California, USA.

How much is nekoite worth?+

Typical asking prices fall in the range of $20-150 per specimen depending on size and quality. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like nekoite?+

Nekoite is most often confused with Okenite, Gyrolite, Tobermorite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with nekoite?+

Nekoite commonly co-occurs with Apophyllite, Calcite, Prehnite, Thaumasite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nekoite form in?+

Nekoite typically forms in metamorphosed limestone. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nekoite used for?+

Nekoite is used in collector.

Find nekoite on the map

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