Brownstone

Brownstone is a brown Triassic-Jurassicsandstone which was once a popular building material. The term is also used in the United States to refer to a townhouse clad in this material.

In the 19th century, Basswood Island, Wisconsin, was the site of a quarry run by the Bass Island Brownstone Company which operated from 1868 into the 1890s. The brownstone from this and other Apostle Islands quarries was in great demand, and brownstone from Basswood Island was used in the construction of the first Milwaukee County Courthouse in the 1860s.

Hummelstown brownstone is extremely popular along the East Coast of the United States of America, with numerous government buildings from West Virginia, Pennsylvania, New York, Maryland, and Delaware being faced entirely with the stone. The stone comes from the Hummelstown Quarry in Hummelstown, Pennsylvania, a small town outside of Harrisburg, Pennsylvania. The Hummelstown Quarry is the largest provider of brownstone on the east coast. Typically the stone was transported out of Hummelstown through the Brownstone and Middletown Railroad or taken by truck up to the Erie Canal.

Portland brownstone, a.k.a. Connecticut River Brownstone, is also very popular. The stone from quarries located in Portland, Connecticut, and nearby localities was used in a number of landmark buildings in Chicago; Boston; New York City; Philadelphia; New Haven, Connecticut; Hartford, Connecticut; Washington, D.C.; and Baltimore.

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