Most of Ontario was not colonized until the first wave of Empire Loyalists arrived in the 1780s. Not long after, about 1790, the first settlers arrived in Ancaster and Dundas, both of which had the advantage of streams with good locations for mills, and quarries with stone suitable for building. The earliest surviving stone buildings were constructed from local dolomite rubblestone, perhaps as early as 1820. Beginning in the 1830s, the superiority of the local Whirlpool Sandstone (basal Silurian) was recognized, and better buildings in Ancaster, Dundas and Hamilton were faced mainly with Whirlpool used as dimension stone: this stone has been widely misidentified as “local limestone” by architects and historians. Even the exact locations of the quarries in Ancaster and Dundas are no longer known; their production was evidently exhausted by the 1890s, at which time the dominant building stone in the Niagara Peninsula became “Queenston stone,” Lockport (Gasport Member) dolomitic limestone, first extensively quarried by Robert Gibson in 1884. An alternative stone, used mainly in Hamilton and Waterdown, was Lockport (Eramosa Member) dolomite.

In the region from Guelph to Galt (now Cambridge) the preferred stone was the Guelph dolomite. Galt, originally settled by Scots, still preserves a variety of stone buildings, industrial, religious and domestic, constructed mainly from Guelph dolomite, but also making extensive use of amphibolite and granite derived from “field stone” and erratics of glacial origin.

Stone was used in the three major canal systems built in the 1820s and 1830s (Welland, Grand River, Rideau), and in the railways built in the 1850s. This transportation system, in turn, allowed widespread use of stone imported from the USA (Indiana limestone, Ohio sandstone) in towns, such as Toronto, that lacked a local source of good stone.