(Sharecast News) - Gold miner Centamin said 2018 gold production fell 13%, despite a boost from the final quarter in what it described as an "operationally challenging" year.Full-year production from the Sukari mine in Egypt was 472,418 ounces, in line with previous lowered guidance offered in December, but lower than the 505,000-515,000 ounces it forecast in August.Fourth quarter production rose 17% quarter-on-quarter to 137,600 ounces, driven by higher grades from open pit and underground operations, Centamin said.Full year production guidance was revised during the course of 2018 in response to lower grades delivered from the open pit in the first half, disruption to the underground stoping sequence in Q2, caused by a damaged rig; and unplanned dilution from the cascading stopes in the Amun underground."We look forward to 2019, where the focus remains on ensuring delivery of grade and as such gold production from Sukari, supported by tight cost control across all areas of the organisation and returns for our shareholders," said chief executive Andrew Pardey.