Although our Puritan ancestors scorned the pretense of personal vanity, mirrors were part of their early colonial households, if used only to glimpse their appearance before they wended their way to service on the Sabbath.
Although the Venetians undoubtedly made the first looking-glasses, having discovered the art of coating plates of glass with an amalgam of tin foil and mercury, it was not until 1673 when the first English-made looking-glass plates were cast.
In 1835, a German, Justus Von Liebig, invented the modern mirror-making technique of chemically coating glass with silver (now often aluminum). In the nascent United States, looking glasses were mostly imported from England, and were expensive. With the exception of a few crude homemade examples, there is little indication that mirrors were made here before the second half of the eighteenth century.
The introduction of glass mirrors gave rise to a new industry — the making of mirror frames. Many cabinetmakers in colonial America were versatile men willing to do anything for their customers, from taking down and setting up beds, making and repairing furniture, to fashioning the coffins for their last journey. Among them were men who knew how to carve a frame and even knew how to resilver mirrors.
The different styles are characteristic of certain periods or designers, and it is the frame and the date of manufacture, rather than the glass that indicates value. Distinct looking-glass styles are associated with important 18th century cabinetmakers and designers: Thomas Chippendale, George Hepplewhite, and Thomas Sheraton.
As mirror styles changed, although glass was still cast in one piece of limited size, long frames with two glasses, one above the other, became popular. This style of mirrors became coveted wall decorations and it was fashionable to remodel the old ones.
Craftsmen advertised their willingness “to alter and amend old looking glasses.” If you broke a mirror, it really was bad luck, since they were so expensive. Many times a new mirror frame was fashioned to conform to the shape of the broken mirror fragment.
These “Make Dos” can command high prices in the antique marketplace. The glass is often an indicator of a mirror’s time period and age. Mirror glass that shows a slight waviness or random bubbles may indicate the glass is old, but does guarantee the piece is antique. The reflective coating used on the back of the glass is what makes a sheet of glass become a mirror and the materials used to create this effect have changed greatly over the years.
Old mercury glass was created by a reaction between mercury and tin, causing the mirror-like substance to adhere to the glass. Old mercury mirrors age to create a somewhat sparkly effect, so if a mirror has a crystalline appearance behind the glass, it likely is an antique.
Whether made with tin and mercury or a thin sheet of silver, glass tarnishes or oxidizes over time. A true antique mirror in a frame typically shows oxidation that is greatest near the bottom, as moisture from cleaning the mirror seeps down behind the frame and may soak the mirror backing at times. If the oxidation or the mirror glass looks too even or uniform, the piece may not be antique.
Although antique mirrors retain their practical value for us to see ourselves, they also provide a decorative feature that enhances the style of a room by increasing a sense of light and space and even adding a touch of glamour.