Mill Lake stone quarry, better known to locals as Hall’s Quarry, was originally mined starting in 1900 by Mr. W.R. Hall and still remains today in the Hall family. The rock in the quarry is described as “finely laminated, pink, grey and white biotite gneiss” and include beautiful granites (of all shades) and quartz. Some of that stone can be seen on the on the Parry Sound Court House and Registry Office foundations, which was constructed in 1921-22 and still serves the same function today as it did nearly 100 years ago.