Bornite mineral specimens collected from Congo, Africa exhibiting a vibrant iridescent blue colouration and a metallic lustre. Bornite is an important copper ore but it also contains iron and as such the mineral is very dense; people often remark at its surprising weight when initially picking it up. Although popular among those interested in geology and mineralogy, bornite also has a niche in the gemstone gift market. This is partly due to its bright colour but also when treated with acid the mineral can develop an even more vibrant blue colour. The treated mineral is often sold on as 'peacock ore' and we sell this also. These bornite specimens are supplied in a large ( 4 cm x 4 cm ) magnification box to enhance the viewing of the sample. An interesting addition to any collection both for educational and display purposes, excellent for children ( +7 ) or as gift for mineral enthusiasts and those interested in geology.