I've just received the 1854 marriage certificate for one of my wife's ancestors. His name Robert Roberts, residence at time of marriage written as Maesydref. His wife was Hannah Morris from Mold. The ceremony occured in the Mold parish church.
On the 1861 census Roberts birthplace is recorded as Mold in 1834.
According to Google Earth Maesydref is in Glamorgam. Isn't that a bit far from Mold? Was there a coal mine in Flintshire called Maesydref?