Chestnut Street and Purple Glass

Chestnut Street is often considered the prettiest street on Beacon Hill. Number 29A is the oldest house built by the Mount Vernon Proprietors.  It was designed by Bulfinch in 1799, the year that the street opened.  The purple glass that you see in the windows is actually a manufacturing error. It was part of a shipment of glass produced in Hamburg, Germany and shipped to the U.S. around 1820. An excess of manganese in the glass caused the glass to turn purple when exposed to sunlight. As time went on, the purple glass became associated with the wealthy homes on Beacon Hill, so manufacturers began to reproduce it. To tell whether or not the glass is authentic, look to see if the color is uneven. Manufactured purple glass is usually uniform in color.