To Remove Centuries-Old Dirt & Grime from Porcelain, Try an Ultrasonic Cleaner
by David Pike (07/09/12)
Some people like their antiques dirty. I prefer them clean.
One very good way to get the exposed parts of the foot and any chipped areas of porcelain clean is to use an ultrasonic cleaner. These cleaners use sound waves in the ultrasonic range to vibrate the piece which loosens dirt that usually can’t be dislodged. I have used them to clean both underglaze-decorated porcelain and overglaze enameled porcelain with good effect. I would warn against using ultrasonic cleaners with overglaze enamel that is in poor condition, as it is possible to vibrate the enamel off the piece. I have never had enamel that is fused well to the glaze come off, and I have cleaned hundreds of pieces, but I guess it could happen.
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