Opal, Pearl, Emerald, Tanzanian zoisite, Malachite, Emerald, Ruby, Lapis lazuli and Coral.

2.

Organic gemstones, opals, turquoise, emeralds.

3.

Jewelry without borders and micro-inlays cannot be cleaned by ultrasonic cleaning machine to prevent jewelry from falling off.

4.

Generally speaking, pearl ornaments and jade articles cannot be cleaned by ultrasonic wave, nor can gems with serious cracks be cleaned by ultrasonic wave.