Gemfields's H1 results affected by India's demonetisation programme

Gemfields -- whose revenue was $51.0m, from $94.0m -- said the one-off Indian demonetisation programme had affected the company's auction schedule.

"This has resulted in the requirement to reschedule one higher quality rough emerald auction into the second half of the financial year, the results of which were announced today, and the consequent removal of another higher quality emerald auction," the company said.

"The impact of this will see a material reduction in annual revenue and EBITDA for this financial year only."

Gemfields separately said its Lusaka emerald auction last week produced revenues of $22.3m, with average per carat sales value of $63.61, the third highest to date. At the auction, it sold 349,935 carats from the 417,060 offered.

Meantime, looking ahead, Gemfields said the outlook for Montepuez remained encouraging both in terms of operational and financial performance.

"The recently upgraded processing plant will allow the Company to achieve its planned increase in production over the coming periods," the company said.

It added that low first-half production at Kagem mine was expected to reduce targeted total production of rough emerald and beryl to 25-30m carats for full-year 2017, from pprevious guidance of 30-35m carats.

"The company, however, remains confident that it will be able to achieve its planned ramp up in emerald and beryl production over the coming years."

At 10:41 GMT, shares in AIM-listed Gemfields were down 6.93% to 47p each.