Presented below are links to some other web sites which feature gem, rock, and mineral postage stamps.
Meteorite Stamps and Coins
Stéphane Gigandet
A collection of stamps figuring photos or images of minerals, cristals, gems, rocks, fossils and meteorites from around the world.
Richard Busch
Gem, Rock, and Mineral Postage Stamps
From Around the World
Hans Marquardt
Mineralogie - Paläontologie - Geologie
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