Gemstones are often treated for many different reasons. Some stones are treated to enhance colour and appearance whilst others are treated to make them more durable. Learn more about the common stone treatments used on Gemondo gems here.

 

TYPES OF TREATMENT

HEAT

Heating involves exposing gems to high temperatures to change colours and reduce the appearance of inclusions.

IRRADIATION

Irradiation is the process of using radiation to alter a stone's colour. This process is often used alongside heating,

DYEING

Dyeing involves applying a colour to a gemstone.

BLEACHING

Bleaching uses chemicals to strip or weaken a given colour within a gem. Dyeing may also be used along with bleaching to achieve a desired mix of shades.

HIGH PRESSURE, HIGH TEMPERATURE (HPHT)

Exposing stones to both high pressure and high temperature to alter colour.

IMPREGNATION

Porous gems are coated or impregnated with a layer of wax, plastic, resin or similar.

COATING

Gems are coated with a thin film or painted to give the appearance of a particular colour. Coating can occur on one side of a stone or many.

OILING

Oiling is the process of filling stones with oil to improve colour and reduce the appearance of flaws.

DIFFUSION

Diffusion is achieved by adding elements such as iron during the heating process to enhance gem colour.

 

TREATMENTS BY GEMSTONE

Gemstone Treatment

Agate

Dyed, Heated

Amazonite

Dyed, Impregnated

Amber

Heated, Dyed, Heating & Pressure

Amethyst

Heated, Irradiated

Aquamarine

Heated

Blue Chalcedony

Dyed

Blue Topaz

Irradiated

Chalcedony

Dyed

Chrome Diopside

No treatment applied

Chrysoprase

No treatment applied

Citrine

Heated, irradiated

Carnelian

Heated, dyed

Diamond

Heated, heating & pressure

Emerald

Dyed, oiling, resin

Fire Opal

No treatment applied

Garnet

No treatment applied

Green Quartz

Heated, irradiated

Hematite

No treatment applied

Iolite

No treatment applied

Jade

Impregnated, wax, dyed

Labradorite

Coating

Lapis Lazuli

Impregnated, dyed

Malachite

Coated, impregnated

Marcasite

No treatment applied

Moonstone

Oiled to improve clarity

Mother of Pearl

Dyed

Mystic Topaz

Coated

Obsidian

No treatments applied

Onyx

Dyed

Opal

Impregnated with colourless oil, wax and resin, dyed

Oro Verde

Heated, irradiated

Pearl

Bleached, dyed, irradiated, polished, lustre enhanced

Peridot

Oiling, filling

Pink Topaz

Heated, irradiated

Pink Tourmaline

Heated, irradiated

Prehnite

Lustre enhanced

Quartz

Heated, irradiated

Rhodolite Garnet

No treatments applied

Rock Crystal

No treatments applied

Rose Quartz

No treatments applied

Ruby

Heated, dyed, irradiated, diffusion

Sapphire

Heated, diffusion, irradiated

Smokey Quartz

Irradiated, heated

Spinel

Heated

Tanzanite

Heated

Tigers eye

Heated

Tourmaline

Yellow/Orange: Heated, irradiated

Green/Blue: Heated, oil or resin

Triplet Opal

No treatments applied

Tsavorite

No treatments applied

Turquoise

Impregnated, dyed