The first answer to what your china is worth is what someone is willing to pay for it. You can start with looking on ebay and see what china like yours has sold for or you can find websites that sell your specific china brand and pattern. If the pattern is discontinued you will have to use a dealer who specializes in that brand of china to determine value. If you are looking to sell to a dealer then don't expect to get the price that he would sell it at as the dealer has to make a profit as well. I would expect 50-60% of what he would sell it for as the price you will be offered. If that isn't good enough then try ebay or craig's list and see if you can sell it. You can always put in a reserve to make sure you get the minimum amount you are looking for. In the end though your china is still only worth what someone will pay you for it.