As a single person living alone, I frequently use china in a microwave oven. I would like to know if this frequent exposure to the microwave is harmful to glazed pottery or glass? - B.U., Salt Lake City.

The most likely problem occurs not to the china but to the microwave. If the china has a metallic band of gold or platinum on the rim, it could cause the microwave to spark. Microwave instructions are explicit: Don't put metallic objects in the microwave.Standard advice about caring for fine china and stemware, passed on to us by ZCMI china and glassware buyer Bill Patterson, follows:

- If you put china in a conventional oven, start with a cold oven and gradually bring up the temperature. Sudden changes in temperature could cause the china to crack.

- Fine china is guaranteed to be dishwasher safe. However, use no more than the recommended amount of detergent, load the dishes properly (dishes shouldn't touch each other) and let them go through the entire cycle. (Don't remove the dishes early and wipe them dry. You could actually damage the metallic rim if the plate is still hot.)

(Editor's note: Although manufacturers guarantee china to be dishwasher safe, common sense tells us that daily exposure to high temperatures and dishwasher detergent could dull or wear thin the metallic rim over a lifetime.)

"In a lifetime of typical use, fine china will not show any ill effects," says Patterson. "In the unlikely event of a problem, it's guaranteed by the manufacturer."

- Don't put crystal stemware in the dishwasher. "First, there is tremendous water pressure and things rattle around in there," he says. "The stemware could chip." Second, if your stemware has a metal band on the rim, it, too, could wear thin over a period of time with repeated exposure to the high temperatures and harsh detergent of dishwashers. Patterson says consumers need to differentiate between the possible dishwasher damage to china over an extremely long period and the probable short-term damage to stemware. " Stemware will more likely show damage in a relatively short time." Third, in rare instances lead crystal can cloud with repeated exposure to harsh dishwasher detergents. "Fine stemware should be washed by hand, one piece at a time," says Patterson.