A large free-form boulder opal with colourful patterning throughout this picture stone. 31.42 carats. 37.5 x 15.1 mm / 1.47 x 0.59". 5.3 mm / 0.20" thick. Natural solid boulder...
A large free-form boulder opal with colourful patterning throughout this picture stone. 33.13 carats. 35.4 x 17 mm / 1.39 x 0.66". 5.5 mm / 0.21" thick. Natural solid boulder...
A pair of mis-matched boulder opals with gorgeous purple running through the ironstone host rock. 30.91 carats (total). 2.50 (L) and 3.69 grams (R). Left opal, 18.1 x 16.8 mm...
A large rectangle boulder opal with brilliant rainbow colours. Truly one-of-a-kind. 42.45 carats. 40.8 x 13.6 mm / 1.60 x 0.53". 6.5 mm / 0.25" thick. Natural solid boulder opal....
A large triangle blue and green boulder opal with a dark background. 26.17 carats. 31.4 x 19.8 mm / 1.23 x 0.77". 5.3 mm / 0.20" thick. Natural solid boulder...
A large, free-form violet / deep purple boulder opal with a jet black background. 15.53 carats. 38.8 x 11.1 mm / 1.52 x 0.43". 4.6 mm / 0.18" thick. Natural...
A great triangle boulder opal with blues and purple colours. 12.61 carats. 22.4 x 16 mm / 0.88 x 0.63". 4.6 mm / 0.18" thick. Natural solid boulder opal. Mined...
A triangle boulder opal with fun blue tones. 10.65 carats. 28.6 x 11.7 mm / 1.12 x 0.46". 4.5 mm / 0.17" thick. Natural solid boulder opal. Mined by Sue...
