Big Black/Dark Knobby of Lightning Ridge 34.50cts some blue colours showing 26x22x16mm Lot B4-A130 wk_end_auction Features:Bright Blue centre exposed with

Features:Bright Blue centre exposed with a unique knobby shape

solid chunk of rough seam opal

Dimensions: 25x19x11mm

Grade C — some visible colour but still a gamble if cutting is attempted

⚠️ Gamble Grade A–B (Gamble)Strong bar visible

Big Black/Dark Knobby of Lightning Ridge 34.50cts some blue colours showing 26x22x16mm Lot B4-A130 wk_end_auction Features:Bright Blue centre exposed withBig Black Dark Knobby Opal Rough 34. 50cts Lot: B4 A130Size: 26 x 22 x 16mmWeight: 34. 50 caratsOrigin: Lightning Ridge, Australia This big black dark knobby opal rough from Lightning Ridge features some blue colors showing, making it an interesting piece for lapidaries and collectors. With its deep base and natural formation, this opal presents a great opportunity for cutting and exploration. Natural & Untreated Some Blue Color Visible Authentic