Goethite pseudomorph after Marcasite      White Desert, Farafra Oasis, New Valley, Egypt.  This perfect floater measures 3.8 x 3.8 x 3.4 cm and shows no damage, contacts or rubs.  The crystal form of this one is not the typical "cocks comb" form of marcasites but the crystals are somewhat blocky in shape.  It is a fine example of this material.  $60