Arkose

A sandstone with lots of pink feldspar, eroded quickly from nearby granite.

Arkose specimen — Photo: James St. John, CC BY 2.0, via Wikimedia Commons

How to identify arkose

Pinkish sandstone with chunky feldspar grains.
Angular grains of quartz and feldspar.
Gritty texture.

Often confused with

Sandstone
Ordinary sandstone is mostly quartz.
Compare side by side
Granite
Granite crystals interlock; arkose grains are cemented.
Compare side by side

Where it's found

Uluru, Australia
Flatirons, Colorado
Torridon, Scotland

Uses

Building stone.

Rock tumbling

Not suitable for tumbling.

Did you know?

Uluru is a giant block of arkose — its red color comes from rusting iron.

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