YOUR SOURCE FOR COLOR

Australian opal is a hydrated silica gemstone formed when silica-rich water percolated through cracks and cavities in sedimentary rock, depositing microscopic spheres of silica gel that later solidified as water gradually evaporated. These tightly packed silica spheres diffract light — bending and splitting it into its spectral components — which creates opal’s signature play-of-color, a vivid rainbow display that shifts with the angle of light and view. This optical phenomenon makes opal unique among gems: unlike crystalline stones that reflect color from electronic transitions, opal’s colors arise from the physical diffraction of light caused by its internal microstructure, a property intrinsic to precious opal forms.

Australia is the world’s foremost source of natural precious opal, producing the majority of the globe’s supply and hosting several famous deposits that yield distinctive opal types. Among the most prized is black opal, particularly from Lightning Ridge in New South Wales, where the dark body tone provides a dramatic backdrop that makes the play-of-color especially intense and visible; lighter-toned light and crystal opals, often found around Coober Pedy in South Australia, display vibrant, translucent to transparent patterns; and boulder opal from Queensland forms in ironstone host rock, with opal seams creating bold color contrast directly against the matrix. Each of these Australian varieties reflects subtle differences in formation environment, body tone, and internal structure — factors that influence both their scientific character and aesthetic appeal.