GemOro Superior Instruments
14
PRELIMINARY GUIDELINE FOR GEMSTONE CLEANING
GEMSTONE
TOUGHNESS
STEAM
Alexandrite
excellent
usually
Amazonite
poor
never
Amber
poor
never
Amethyst
good
risky
Aquamarine
good
usually
Citrine
good
risky
Coral
fair
risky
Diamond
good
usually
Emerald
poor
never
Garnet
fair
never
Iolite
fair
risky
Lapis Lazuli
fair
never
Opal
fair
never
Pearl
good
never
Peridot
fair
never
Ruby
excellent
usually
Sapphire
excellent
usually
Spinel
good
usually
Tanzanite
fair
never
Topaz
poor
never
Tourmaline
fair
risky
Turquoise
fair
never
Variscite
fair
never
Zircon
fair
risky