What causes the spots on these mirrors?

The spots, known as foxing, occur when moisture seeps behind the glass over decades and reacts with the silver or mercury backing. This chemical breakdown creates the atmospheric, cloudy patches that define the look of an antique mirror plate.

Are these plates original to the frames?

Many retain their original mercury glass plates, though some eighteenth and nineteenth-century pieces have received replacement plates during their long histories. Examining the backboards and the way the glass is secured helps determine if the plate has remained with the frame since manufacture.

How do I hang a heavy antique mirror?

Due to the substantial weight of solid wood, gesso, and thick glass plates, these mirrors require secure wall fixings attached directly to structural studs. Professional mirror hangers often use french cleats or heavy-duty brackets rated for the specific weight of the piece.

Where were overmantel mirrors placed?

Overmantel mirrors were specifically manufactured to hang on the wall directly above a fireplace mantelpiece in period reception rooms. Their horizontal proportions were designed to complement the width of the hearth and reflect light from the room's windows.