Which gemstones CANNOT be put into an "ultra-sonic" cleaner? - 3 photos.

 First of all just what is an "Ultra-Sonic Cleaner"? It is an apparatus that emits sound waves through a liquid medium (water).This tankful of water has one or two 'sound emitters' built underneath the tank.

 The sound vibrates at a constant level of 40,000 cycles PER SECOND, which is above the level of normal hearing.

 This high level of sound being emitted, vibrates the crystalline structure of that stone and in turn literally shakes (vibrates) any dirt off of the stone, or the metal. This is basically the simple process, now which stones cannot be immersed into the 'cavitation' - shaking process?
 

 My preference is to 'suspend' the jewellery item, but to clean any loose gemstones these can be placed into jar of "Methyl Hydrate" aka Alcohol.

 You can see the two 'sound speakers' that are working in tandem underneath the tank.

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   Here is the list of 10 stones that must never be used.

1) PEARLS: As these are organic items, please refrain from immersing them into this cleaning process. The 'thin skin' of the pearl will be ruined within seconds. Mohs Scale  is at 2.5.

2) OPALS: These are very delicate stones  Mohs scale @ 5 - 6.5

3) AMBER: Amber is basically a sap that is found in trees. Mohs scale @ 2 - 2.5

4) TURQUOISE: The stones will loose their colours. Mohs Scale 5-6.

5) ONYX: Some of these stones are colour dyed Mohs Scale  6.5 - 7.

6) AQUAMARINE: These are soft @ 5 - 8 on the Mohs Scale.

7) EMERALD: Don't put these stones into cavitation, or the stone will shatter. 

Mohs @ 6.5.

8) LAPIS LAZULI: Very soft at 5-6 on the Mohs Scale. Don't use this stone.

9) CORAL: Don't even think of cleaning this stone. Mohs Scale @  3-4.

10) 'FRACTURE FILLED' DIAMONDS: Many diamonds have inclusions and for appearances the inclusions are filled to camouflage the fractured crystalline veins.

  What gemstones may be placed in the ultrasonic machine? There are two stones they are RUBY & SAPPHIRE, why only two? These belong to the "Corundum" family of stones.

Corundum are a very strong crystal which are on the 8-9 Mohs Scale of Hardness.

 Hoping that this essay has been much help to you. Regards, eh! Gerry Lewy.