|Nancy I have to disagree with that as I tumble polish and harden ALL of my wire jewelry pieces in a rotary tumbler. I have forgotten the tumbler in the on position and let it run all night! Both the cameo and the gold filled wire was in very good condition. BUT all you need is about two hours of tumbling for a great job.
The tumbling works exceptionally well with wire sculpted pieces that may not be hard and firm. Two hours of tumbling with a inexpensive rotary tumbler and some steel shot will do the trick.