What does China mean as in How is your old China?

There are types of dishes that are made of china, a ceramic type of material.

So, when someone is asking "How is your old china?", they are asking about the age of your china dinnerware or porcelain figurines.

The ceramic dinnerware was originally named 'chinaware' because it originated in the country of China.

How's your old china?, is cockney rhyming slang for how is your friend.

China plate = mate