Can diamond, clean and well set go in an ultrasonic tank?

Yes. A sound diamond takes anything. The risk is the setting, not the stone.

Can diamond with a visible feather go in an ultrasonic tank?

No. Cavitation finds the fracture and opens it. Steam can too if the piece is cold.

Can fracture filled or clarity enhanced diamond go in an ultrasonic tank?

No. The filler is glass. Heat and cavitation both drive it out.

Can ruby and sapphire, untreated go in an ultrasonic tank?

Yes. Corundum is hard and takes a tank well.

Can ruby with glass filling go in an ultrasonic tank?

No. Common in low cost goods. The filling will not survive either machine.

Can emerald go in an ultrasonic tank?

No. Almost every emerald is oiled or resin treated. A tank strips it and the stone goes cloudy.

Can opal go in an ultrasonic tank?

No. Porous and full of water. Heat and vibration both crack it. Wipe only.

Can pearl and mother of pearl go in an ultrasonic tank?

No. Nacre is layered and glued to a bead. Damp cloth, nothing more.

Soak check • what can go in the tank • GemOro

Before you switch anything on

Soak check

Cavitation does not know the difference between dirt and a filled fracture. Steam does not know the difference between grime and plating. Pick the piece and we will tell you which of our machines it can stand, and which it cannot.

What are you about to clean?

How the table breaks down

6take an ultrasonic tank

13must stay out of one

5go in only with care

24kinds of piece listed

The whole table

Care means it will probably survive and we would still not risk a customer piece on it.

Piece	Ultrasonic	Steam	By hand	Why
Diamond, clean and well set	Yes	Yes	Yes	A sound diamond takes anything. The risk is the setting, not the stone.
Diamond with a visible feather	No	Care	Yes	Cavitation finds the fracture and opens it. Steam can too if the piece is cold.
Fracture filled or clarity enhanced diamond	No	No	Yes	The filler is glass. Heat and cavitation both drive it out.
Ruby and sapphire, untreated	Yes	Yes	Yes	Corundum is hard and takes a tank well.
Ruby with glass filling	No	No	Yes	Common in low cost goods. The filling will not survive either machine.
Emerald	No	No	Yes	Almost every emerald is oiled or resin treated. A tank strips it and the stone goes cloudy.
Opal	No	No	Care	Porous and full of water. Heat and vibration both crack it. Wipe only.
Pearl and mother of pearl	No	No	Care	Nacre is layered and glued to a bead. Damp cloth, nothing more.
Turquoise, coral, amber, jet	No	No	Care	Porous or organic. They absorb the solution and stain.
Tanzanite	No	No	Yes	Perfect cleavage. It splits along a plane and vibration is exactly the wrong input.
Malachite, lapis, azurite	No	No	Care	Soft and often waxed. The wax comes off before the dirt does.
Peridot and moonstone	No	Care	Yes	Both dislike sudden heat and both are brittle enough to mind cavitation.
Topaz and citrine	Care	Care	Yes	Fine if flawless, but thermal shock is a real risk on a cold stone.
Amethyst and other quartz	Yes	Care	Yes	Quartz takes a tank. Deep colour can fade with repeated heat.
Garnet and spinel	Yes	Yes	Yes	Tough, unfilled, no cleavage worth worrying about.
Cubic zirconia and moissanite	Yes	Yes	Yes	Both are durable and both come out of a tank looking new.
Any doublet or triplet stone	No	No	Care	Two pieces held with cement. The tank separates them.
Glued or channel set costume pieces	No	No	Care	If the stone is held by adhesive, assume the adhesive loses.
Plain gold, silver and platinum	Yes	Yes	Yes	Metal alone is the easiest thing you will clean all day.
Silver with an applied patina	Care	Care	Yes	A tank will lift the blackening out of the recesses along with the dirt.
Gold plate and vermeil	Care	No	Yes	Plating is thin. Steam pressure at close range strips it.
Worn or loose prongs, any stone	No	No	Care	Check with a loupe first. A tank does not loosen good prongs, it empties bad ones.
Watch cases and bracelets, sealed	Care	No	Yes	Bracelet yes, head no, unless you know the gaskets are sound.
Eyeglasses with coated lenses	Care	No	Yes	Frames are fine. Coatings and glued lens rims are not.