Electric blue and green fire cuts through warm chocolate-brown ironstone, forming bold flashes that move with the light. Boulder opal forms when precious opal develops naturally within ironstone, with the host rock left intact to support and frame the color. This structure gives boulder opal its durability and its distinctive contrast, with the ironstone acting as a natural backing rather than an added treatment. Australian boulder opal is valued for this combination of stability, depth, and strong directional color play.
20.010 cts / 21.2 x 16.1 x 6.9 mm
Estimate: $215 - $245