Emerald miner Gemfields first-half core earnings fall

March 3 (Reuters) - Precious stones miner Gemfields Plc's core earnings for the first half fell about 8 percenthurt by higher production costs.

Core earnings or earnings before interest, tax, depreciationand amortization (EBITDA) for the six months ended Dec. 31 fellto $18 million from $19.5 million a year earlier.

However, the company, which produces about a fifth of theworld's rough emeralds, said revenue soared 137 percent to $65.7million boosted by strong demand at its auctions.

Gemfields said unit production costs rose to $0.85 per caratfrom $0.57 per carat a year earlier.

Gemfields Grou.