Bronte Steam Mill was built in 1858, two years after the completion of the harbour. The mill was located on the west-side (water side) of Bronte Rd. With solid brick walls and a 4' thick stone foundation the mill was a very sturdy structure.The mill was always powered by steam, never water.
The first role of the mill was a grist mill (for grinding grain into flour). The Steam Mill was one of the largest in Ontario at the time, it had 'five run of stone' allowing the mill to process grain into flour for more than one farmer at a time, ground to various degrees of fineness
In the twentieth century the mill changed from a grist mill to a stamping mill and began to produce a variety of metal products, including license plates for Alberta, Manitoba, New Brunswick, Nova Scotia and Quebec (the Ontario contract went to a new manufacturing plant at the Guelph Correctional Facility). During the year of George VI's Coronation, the mill (renamed The Bronte Chaplet and Stamping Co.) made painted metal plaques embossed with the royal couple, which were intended to be mounted on the front bumper of a car.
For the duration for WWII the mill stopped regular production to help out with the war effort. The mill fabricated gas mask components for the army, electrical junction boxes for the air force, and heavy brass eye bolts for the navy.
Due to a large fire in 1950, the roof and the top floor blew off, the mill was restored but was eventually demolished in 1987 when the property was sold to developers to build what is now the Stoneboat Quay condominiums. Before its demise, the final role for the mill was a storage warehouse containing pots and pans.