 Vivid blue spinel with white carbonate in calc-silicate rock. | Cobalt-blue spinel is a rare gemstone. The most significant source of the gems is Vietnam. The karst mountains of An Phú, near Luc Yen in Vietnam, is the world's only source of the most coveted of all gem blues. The amount being produced is so tiny, that a decent clean gem of even half a carat is a rarity. |  |
 Other gems found on Baffin Island include Beluga sapphires, used in the Queen's sapphire jubilee brooch, and lapis lazuli. | Researchers analyzed 14 occurrences of spinel on Baffin Island, including two of cobalt-blue spinel, to better understand how it forms. "It's finding the right chemical components in the right concentration." Baffin Island spinel contains up to 500 parts-per-million of cobalt, giving it a vivid blue comparable to the best in the world. |  |
