Traditional gilders compo

Compo is a mouldable substance that has a plastic consistency which allows it to be worked either by hand or more usually pressed into moulds to produce decorative work. It was favoured by Robert Adam and others from the middle of the eighteenth century in England. It's now most commonly seen as part of gilded mirrors and picture frames. Frames made using compo tend to be heavier than those made in wood and as the material ages, there is a tendency for it to crack. This may be caused by futher drying out of the composition or, the continued movement of the wooden frame beneath.