Wardsmithite is a very rare hydrated magnesium calcium borate mineral discovered in the borate deposits of California. It typically occurs as small, clear, dodecahedral crystals associated with other borate minerals in evaporite beds. Due to its scarcity and solubility, it is strictly a specimen for advanced mineral collectors.

Hardness

2.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareBorate Mineral family

Wardsmithite

Hardness: 2.5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this wardsmithite?

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 wardsmithite with a known reference. Wardsmithite sits at Mohs 2.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Wardsmithite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Wardsmithite 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: cubic. Typical habit: dodecahedral crystals.

Often confused with

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

mineral

Borax

Mohs 2-2.5

How to tell apart: Luster reads vitreous on Wardsmithite and vitreous to earthy on Borax.

How to tell apart: Luster reads vitreous on Wardsmithite and vitreous to pearly on Kernite.

Compare →

Often found alongside wardsmithite

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

All properties

Chemical formula: Mg₃Ca₄(B₁₀O₁₈)₂·28H₂O
Mohs hardness: 2.5
Density: 2.25 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Cubic
Crystal habit: Dodecahedral Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Evaporite Deposits
Typical price: $50-300 per specimen

Where rockhounds find wardsmithite

Classic worldwide localities

Kramer deposit, Boron, California, USA

Field-hunting tip

Look in evaporite deposits country — that is the host setting where wardsmithite typically forms. If you start seeing borax, kernite, colemanite in float, you are in the right ground. Field specimens usually show a dodecahedral crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify wardsmithite?+

Mohs hardness is 2.5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is wardsmithite found?+

Notable localities include Kramer deposit, Boron, California, USA.

How much is wardsmithite 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 wardsmithite?+

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

What minerals are found with wardsmithite?+

Wardsmithite commonly co-occurs with Borax, Kernite, Colemanite, Ulexite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does wardsmithite form in?+

Wardsmithite typically forms in evaporite deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is wardsmithite used for?+

Wardsmithite is used in collector.

Find wardsmithite on the map

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