MANY people who view auction sales will see dealers and serious collectors alike picking up pieces of porcelain and biting on them as if they haven't eaten for a month.

Well, they may be hungry - but only to find out if the particular mouthful in question has been restored or not. Damaged porcelain is worth a fraction of a perfect example.

A fairly foolproof method is to examine the piece in question with an ultra-violet light, but in the absence of such technology a delicate bite to the suspected area of restoration can help. With a perfect example it feels as if the teeth are trying to chew on a piece of glass; a restored piece will feel like they are sinking into a bar of soap or putty.