Bone ash and % are not accurate ways to judge quality. While Corelle is very low priced dinnerware Wedgwood is some of the most expensive on the market, and is rarely used daily. Are you planning to never use a dishwasher? Or put this into a microwave? Many patterns cannot go into either. Part of why these are expensive is because of how high maintainence their care is. So many patterns contain lead that is sealed under finishes that don't last and cause exposure to lead. I use Polish pottery or newer Fiestaware but while these are safe and without contaminates they aren't thin bone china either. Lead safe mama has a lot of tested dish patterns if you want safe durable dishes.