Horseshoe nail, Iron, untreated. Length 46mm

In the past, many windows were not designed to be opened. Forged iron was expensive, so typically only a few window sashes were fitted with hardware. This was common well into the 19th century, and has persisted into our time on outbuildings and farm buildings. Nails used for nailing window sashes must have a conical shape to be easily removed without splintering the frame wood (modern wire nails are completely unsuitable in this context). Furthermore, the nail should have a blunt head, to avoid damaging the window sashes when bent in. Therefore, horseshoe nails, or sometimes studs, which both have these properties, were often used.