Rocksday

Dolostone

A limestone-like rock made of the mineral dolomite rather than calcite.

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

How to identify dolostone

  • Gray to cream, often sugary.
  • Fizzes only weakly — or only when powdered.
  • Weathers to a buff color.

Often confused with

Where it's found

  • The Dolomites, Italy
  • Niagara Escarpment
  • Midwestern United States

Uses

Crushed stone and building stone.

Rock tumbling

Can be tumbled with care.

Did you know?

A tough dolostone layer forms the lip of Niagara Falls.

Think you could spot it from a blurry close-up?

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