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.

Stage One


Begin by planing a piece of walnut to make wood shavings.



The wood shavings are placed in a lidded container with ammonia.


Stage Two

Stage Three




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.


Stage Three

Stage Four


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.


Stage Five