The only way to determine if certain tableware represents a lead hazard is to test it for lead. These tests are most useful in detecting high levels of lead. In many cases, they are not sensitive enought to tell whether the dishes meet Proposition 65 standards, or to detect lower levels which might still represent a lead hazard. Many educators have found it very effective to demonstrate the presence of lead in tableware by testing it in front of audiences at presentations, health fairs, and community events.
Some educators distribute lead test kits to participants for testing their dishes at home.
These kits contain chemicals that turn color when applied to a surface which contains significant quantities of leachable lead. There are many brands of lead tests on the market. Each test is different. Be sure to carefully read and follow the instructions provided with any lead test kit. The only way to find out the exact amount of lead dishes leach is to send them to a laboratory for testing.