Lewis's Topographical Dictionary - Waterford County

Bonmahon, a maritime village, in the parish of Ballylaneen, barony of Upperthird, county of Waterford, and province of Munster, 3 miles (S.) from Kilmacthomas; containing 972 inhabitants. This place situated on the coast of St. George's channel, and derives its name from the river Mahon, which rises in the Commeragh mountains, and here falls into the sea. It is much frequented as a watering-place during the summer, and contains several neat private residences and convenient  lodging-houses for the accommodation of visitors; and in the immediate vicinity are numerous houses built for persons employed in the mines. The beach is well adapted for bathing, and the village might be made a place of fashionable resort; but the land being principally the property of the College of Physicians, who cannot grant leases for more than 31 years, very little improvements has been made. The surrounding scenery is very pleasing, and a wooden bridge over the Mahon adds much to its picturesque character. A new church, with a school-house adjoining, has been recently erected on the eastern side of the river, in the parish of Kilbarrymeadan; the school is supported by Lady Osborne.

The valuable mines of this place and in the neighbourhood produce copper and lead, with a portion of silver; they have been worked from an early period, and veins have been opened in several parts and worked to a considerable extent. In 1745 a company rented these mines from Lord Ranelagh for a term of 31 years, under an agreement to give to his lordship one-eight part of all the ore obtained; and the works were carried on with spirit for eight or ten years. They were subsequently worked by Mr. Wyse, who employed 300 mem; and, in 1811, the Earl of Ormonde renewed the enterprise with every prospect of success, but, after a very large expenditure, was induced to desist; they are at present under the management of the Irish Mining Company. The veins are found in some parts of the rock within a few feet of the surface, and none have been worked to a greater depth than 25 yards. Copper ore is observed in many places along the beach. The principal mines are on the property of  the Marquess of Ormonde, on the lands belonging to the see of Waterford, and on those of Lady Osborne and J. Power O'Sea, Esq.- See Ballylaneen.