Are ultrasonic jewelry cleaners safe for cleaning silver jewelry?

Ultrasonci cleaner is safe for cleaning pure silver jewelry, watch, dental tool, glasses and many many other stuff. But In the following condition, it's unsafe:

1. Copper Alloy jewelry plated with gold or silver should not be put in ultrasonic cleaner, and also not wear with gold, platinum or pure silver jewelry.

2. Ultrasonic cleaning is dangerous for the following gemstones:

pearls, opal, amber,tanzanite, emerald, peridot, agate, Amazonite, topaz, aquamarine, turquoise, and gemstones that have cracks or fractures.