Commercial coal mining began in Port Morien in 1720 after a mine had been opened to supply The Fortress at Louisbourg. This was the first commercial coal mine in North America. After the English victory at Louisbourg in 1758, the mine remained in operation for almost ten years.
In 1859, Marshall Bourinot, a fish dealer from Port Morien, re-opened the mine. In 1863, the Belloni brothers, Robert, Charles, and Augustus, of New York, along with their brother-in-law Charles Havenmyer bought out Bourinot and formed the Blockhouse Mining Company. A few hundred meters directly from here to the shoreline a shaft was sunk to the level of the old mine. A slope was driven through the old French workings from the surface at the water's edge. A wharf was constructed so that the coal was hauled directly from the face to the ship's side. A thriving community existed around the mine.
During the American Civil War, the demand for coal could not be satisfied. Coal-bearing vessels could be waiting for months in Morien Bay to be filled. Coal was loaded onto ships at a cost of sixty cents per tonne, and sold in New York for nine dollars. The peak year for the blockhouse mine was 1866, when over 375 men and boys were employed.
A landmark year in Canada for coal miners was 1868. The miners went on strike twice that year for a total
duration of three months. This strike was believed to be the first in Canada. As a result, the coal output dropped significantly to just over fifty thousand tonnes.
Unsteady coal markets and frequent wharf damage due to storms were a financial drain on the company and it finally closed in 1888.
Robert Belloni, one of the owners of the Blockhouse Mine built a beautiful home overlooking Morien Bay in 1863. Reverend Richard Uniacke's description of Robert Belloni's House in his Sketches of Cape Breton, 1864: "The most striking residence was that of the manager, Robert Belloni Esq., which stood upon a partly cleared wooded plateau commanding an extensive and beautiful prospect, especially out to sea... It has two stories with projecting eaves, and gables, and tastefully constructed windows. A handsome verandah forms the entrance towards the southeast; and the principal room which formed the opposite wing of the building terminated in a large bow, giving variety and elegance to the whole structure. The inside is fitted up and furnished with costliness and taste. The view from the verandah of a fine day is really grand..."