(IDEX Online) - Plans to revive the mothballed Ellendale mine - once the world's largest producer of fancy yellow diamonds - have been boosted by "excellent" valuations of bulk samples, says owner Gibb River Diamonds.An independent appraisal of diamonds from the Ellendale 9 Lights stockpile, one of four bulk samples, averaged US$1,443 per carat.The company said updated valuations across a number of prospect areas and stockpiles were "very attractive".In a statement the company said: "Much of this high pricing is driven by the Fancy Yellow diamond component in the valuation parcel. "Previous production from the Ellendale 9 lamproite pipe reported 11.5% of diamonds as Fancy Yellow.""Typically diamond mines worldwide produce less than 0.1% Fancy Yellow diamonds, so Ellendale is truly exceptional in this regard."Valuations from other bulk samples include US$796 per carat for the Ellendale 12 Alluvial Prospect and US$828 per caratfor the E9 East Alluvials.Ellendale, in Western Australia, ceased production in 2015 when Kimberley Diamond Company went into liquidation. It had an exclusive supply agreement with Tiffany & Co. Pic courtesy Gibb River Diamonds, shows Yellow Diamonds from the East Lobe (Far East Pit) at Ellendale