Metal conservator Hal Jacob shows us a simple yet very effective way to patinate the surface of smaller pieces of brass to produce an ‘aged’ effect.
Begin by planing a piece of walnut to make wood shavings.
The wood shavings are placed in a lidded container with ammonia.
The polished brass ball finials are suspended above the ammonia and wood shavings – the fumes generated by ammonia combined with the tannin in the wood shavings will darken the metal.
Place the lid on the container to contain the fumes and create a more concentrated atmosphere.
Leave for between ten to fifteen minutes – or longer should you require a darker effect. Eventually, the metal goes a dark olive colour.