RockWatch (watch)

The RockWatch or Rock Watch was a trademarked brand of wristwatch with a case made of granite, introduced by Tissot in 1985. It was designed by Robert Mazlo.

Tissot claims it was the world's first wristwatch with a case made of natural stone.

When introduced in the U.S., it retailed for $195.

Over 500,000 were sold.

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