The semi black opal is from Lightning Ridge, Australia. 
The opal has nice blue flash, with greens, blue and a touch of red 
Carat weight: 0.83
Body Tone: N7
Brightness: B4 very bright
This ring can be customised to suit your requirements. It can be set in 9K, 14 K, 18k, 22k, or 24k
Ring size: US size 7
Dimensions: 12mm L x 10mm W
Ring weight: 5g