(Sharecast News) - Centamin said on Thursday that gold production at its Sukari mine in Egypt will come in around 2% below full-year 2018 guidance of 480,000 ounces, following lower-than-expected production in October and November.The FTSE 250 gold miner said that combined production of 90,000 ounces in October and November was "slightly" below forecast.While the December mine plan forecasted higher grade from both the underground and the open pit, which would have balanced the quarterly shortfall, lower-than-expected underground grade delivered so far suggests gold poured for the fourth quarter of between 135,000 to 140,000 ounces, meaning annual production will fall short.In addition, Centamin said cash cost of production will be towards the top end of the previously guided range of $625 to $640 per ounce produced and an all-in-sustaining cost will be approximately $900 per ounces sold."Whist the focus remains firmly on sustaining the operational improvements, stringent cost controls and improving gold price means the company continues to be a cash generative business," it said. At 1150 GMT, the shares were down 1.7% to 107.60p.