Official Word:

From peacocks to butterflies to precious minerals, the color-changing effect of iridescence is one of the most stunning visual phenomena in nature. It is especially notable in opals, a mineraloid formed from hydrated silica. One of the most striking - not to mention rarest and most valuable - variants is the black opal, most often found in New South Wales, Australia. Now, however, eagle-eyed drivers may spot the gemstone's multicolored dazzle at their nearest INFINITI Retailer....Read.