This is a beautiful sheet of 5 stamps, issued by Comoros in 2011, displaying minerals. Featured minerals shown include Rutile, Barite, Azurite, Liddicoatite Tourmaline, Apatite, Siderite, Wulfenite, Andalusite, Beryl, and Quartz. The sheet is Michel catalog #2938-43, and is Post Office fresh, mint never hinged, and F/VF.