Borax

A sodium borate from dry lake beds. Clear crystals dry out to white powder in normal air.

Borax specimen — Photo: Aram Dulyan (User:Aramgutang), Public domain, via Wikimedia Commons

How to identify borax

Clear prisms that turn chalky white over time.
Light and soft.
Dissolves in water; sweetish-alkaline taste.

Often confused with

Halite
Halite tastes salty and forms cubes.
Compare side by side
Ulexite
Ulexite is fibrous and silky.
Compare side by side

Where it's found

Boron, California
Searles Lake, California
Turkey
Argentina

Uses

Cleaning products, glass and fiberglass, and slime-making.

Rock tumbling

Not suitable for tumbling. Water-soluble.

Did you know?

From 1883 to 1889, twenty-mule teams hauled borax out of Death Valley.

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