Hello Steve,
Mom has plenty to worry about! My article on:
Silver & Dishwashers
Copyright Jeffrey Herman
KEEP SILVER OUT OF THE DISHWASHER! It’s that simple. There are four
major reasons for keeping your prized sterling and silverplate out of
the “chamber of doom:” (1) Any factory-applied oxidation (the black
patina in recessed areas) will eventually be removed. (2) The harsh
detergent, combined with the washer’s high cleaning temperature, is
much too abrasive for silver-it will eventually turn it grey or
white, with a dull, non-reflective surface. (3) Most older and some
repaired hollow-handled knives are filled with pitch. This
low-melting cement will expand with heat, possibly forcing open a
thin solder seam, or exploding the knife blade out of the handle.
(4) Silver that touches stainless in the dishwasher can create a
chemical reaction, producing black spots and etching on the stainless
blades, requiring the silver to be professionally refinished.
Sterling, like a fine automobile, must be handled with tender loving
care. You certainly wouldn’t drive your Rolls Royce through a car
wash, would you?
Additional silver care advice can be found here:
Jeffrey Herman
Herman Silver Restoration & Conservation