Yowah Nuts are ironstone concretions from Queensland, Australia, that often contain a core of precious opal. When cracked open, they reveal intricate internal patterns of play-of-color, making them highly prized by lapidary artists and mineral collectors.

Hardness

5.5-6.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

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Yowah Nut

Hardness: 5.5-6.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this yowah nut?

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 yowah nut with a known reference. Yowah Nut sits at Mohs 5.5-6.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Yowah Nut leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Yowah Nut typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, red, green, blue, yellow.
5
Look at form & habit
Crystal system: amorphous. Typical habit: nodular.

Often confused with

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

Often found alongside yowah nut

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

All properties

Chemical formula: SiO₂·nH₂O
Mohs hardness: 5.5-6.5
Density: 1.9-2.3 g/cm³
Colors: Brown Red Green Blue Yellow
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Amorphous
Crystal habit: Nodular
Cleavage: None
Rarity: Uncommon
Uses: Gemstone, Lapidary, Collector
Host rock: Sedimentary Ironstone Concretions
Typical price: $20-300 per specimen

Where rockhounds find yowah nut

Classic worldwide localities

Yowah, Queensland, Australia

Field-hunting tip

Look in sedimentary ironstone concretions country, the host setting where yowah nut typically forms. If you start seeing ironstone, quartz, limonite in float, you are in the right ground. Field specimens usually show a nodular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify yowah nut?+

Mohs hardness is 5.5-6.5. It typically shows a vitreous luster. The streak is white. Common colors include brown, red, green, blue.

Where is yowah nut found?+

Notable localities include Yowah, Queensland, Australia.

How much is yowah nut worth?+

Typical asking prices fall in the range of $20-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like yowah nut?+

Yowah Nut is most often confused with Boulder Opal. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with yowah nut?+

Yowah Nut commonly co-occurs with ironstone, quartz, limonite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does yowah nut form in?+

Yowah Nut typically forms in sedimentary ironstone concretions. Working float back to the host body is the standard way to chase a fresh occurrence.

What is yowah nut used for?+

Yowah Nut is used in gemstone, lapidary, collector.

Find yowah nut on the map

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