ANTIQUE MIRRORS AND THEIR HISTORY

Both decorative and practical, mirrors nave fulfilled an important role since the second half of the 17th century. In the 17th and 18th centuries, frames were either inlaid with marquetry, or elaborately carved or gilded, with designs ranging from the grardeur of the baroque to the more fluid rococo carvings perhaps best encapsulated by Thomas Chippendale. In the 19tn century, frames made from plaster on a wire base were common. Known as composition frames, they can be attractive, but are frequently damaged as the plaster chips quite easily. 

French glassmakers used a system which allowed them to make fairly large plates of glass; until the 1770s when the French method was adopted in England and America. Mirrors made in those countries consisted of two or more small plates side by side. In the 18th century, glass was fairly thin, and the reflection obtained was darker than that given by the thicker glass plates that became common with 19th-century mirrors. The reflection is caused by lining the rolled glass with silver foil (mercury-coated tin foil). 

Many period mirror styles are still reproduced today, including the early 19th century bull's-eye-shaped convex mirror, the gilded frame of which is often surmounted by an eagle; modern mirror glass, however, is much thinner than that which it tries to copy. 

If the frame is veneer, understand that on antique furniture veneers were of thick and somewhat irregular widths, rather like home-sliced bread. Modern veneers are thin, with every slice exactly the same width.

Until 1800, all the antique mirror glass in America was imported. Antique glass is thin (less than 1/8 inch thick), variably wavy, and somewhat gray in color. To determine if a piece of mirror is old, hold the tip of a key to the glass. The closer the tip of the reflected Image IS to the tip of the actual key, the more likely it is that the glass is old.