Gemstone Treatment Guide

Gemstone	Treatment Method	Special Care & Advice
Alexandrite	None	Clean with warm soapy water and a soft brush.
Amazonite	Permeated with a colorless wax, paraffin or oil to improve appearance.	Avoid chemicals and do not use ultrasonic cleaner or steamer. Clean with warm soapy water and a soft brush or cloth.
Amber	Sometimes heat treated or dyed to deepen color. Sometimes pressed/compressed with extreme pressure and heat to fuse together small pieces of natural amber.	Avoid chemicals and do not use ultrasonic cleaner or steamer. Clean with warm soapy water and a soft brush or cloth.
Amethyst	Almost all are heated to improve appearance or deepen color.	Do not expose to intense heat. Clean with warm soapy water and a soft brush or cloth.
Aquamarine	Almost all are heated to improve appearance.	Do not use ultrasonic cleaner or steamer. Clean with warm soapy water and a soft brush or cloth.
Citrine	Usually heat treated or irradiated to improve color.	Do not expose to intense heat. Clean with warm soapy water and a soft brush or cloth.
Coral	Usually dyed or bleached to enhance color. Sometimes stabilized with colorless plastic to increase durability and to improve appearance. Sometimes stabilized and compressed under extreme pressure and heat to bind together small pieces of natural material into a larger whole.	Avoid household chemicals, steam and ultrasonic cleaning.
Cubic Zirconia	Synthetic. Some are coated with a product that makes the stone more durable.	Clean with warm soapy water and a soft cloth.
Cultured Pearl	Usually bleached and polished to achieve uniform color and shape. May be dyed or irradiated to produce various colors.	Do not use ultrasonic cleaner or steamer. Avoid contact with cosmetics, hair spray, perfume and household chemicals. Clean with a soft cloth.

Diamond	None	Clean with warm soapy water and a soft brush or cloth.
Black Diamond	There are two different processes that create black diamonds: heat treatment and irradiation. Heat treatment exposes the diamond to high temperatures, which creates graphite residue in the crystal. Irradiation modifies the crystal structure of the stone.	Clean with warm soapy water and a soft brush or cloth.
Emerald	Usually penetrated with oil, wax or resin to improve appearance. Often dyed with color agents.	Do not use ultrasonic cleaner or steamer. Avoid sudden temperature changes, steaming and contact with cosmetics, hair spray, perfume and household chemicals. Clean with a damp cloth or soft brush .
Garnet	None	Clean with warm soapy water and a soft brush or cloth.
Lab-Created Gemstones	Grown in a laboratory, but are chemically, physically and optically identical to natural gems. Natural gems typically have inclusions from the crystallization process, where gases and other minerals mix during the molten stage of stone creation. Lab-created stones rely on a steady, controlled process of applying minerals, heat and pressure, and they usually have few inclusions.	Avoid strong detergents, heat, pressure and ultrasonic cleaner or steamer. Avoid re-polishing or re-cutting of the stone. Color may fade in light or with heat. Clean with warm soapy water and a soft brush or cloth.
Onyx	Always dyed	Avoid exposure to extreme light and heat as stones may fade. Clean with warm soapy water and a soft brush or cloth.
Opal	Occasionally treated with sugar or smoke to enhance the color. Sometimes infused with wax, oil or plastic to enhance appearance and durability.	Do not use ultrasonic cleaner or steamer. Avoid heat and contact with cosmetics, hair spray, perfume and household chemicals. Clean with a damp cloth or soft brush.
Peridot	Sometimes infused with oil, wax resins and/or colorless hardened substance to enhance appearance.	Do not use ultrasonic cleaner or steamer. Avoid sudden temperature changes and contact with harsh chemicals.

Quartz	Usually dyed and/or heat treated to produce different colors. Sometimes surface enhanced with a coating to enhance color.	Avoid abrasives, harsh chemicals, steam, and ultrasonic cleaning. Clean with warm soapy water and a soft brush or cloth.
Rose Quartz	Heated to improve appearance and deepen or lighten color.	Do not expose to intense heat. Clean with warm soapy water and a soft brush or cloth.
Rhodolite Garnet	None	Clean with warm soapy water and a soft brush or cloth.
Rubies	Certified rubies are heat treated with residue to improve appearance. Impurities may also dissolve or become less noticeable after heating. All treatments are permanent and fully disclosed on the IGI certificate.	Avoid strong detergents, heat, pressure and ultrasonic cleaner or steamer. Avoid re-polishing or re-cutting of the stone. Color may fade in light or with heat. Clean with warm soapy water and a soft brush or cloth.
Sapphire	Usually heated to improve appearance. Occasionally irradiated. Commonly diffused along with heat application to create different colors. Yellow sapphire is always diffused.	Avoid strong detergents, heat, pressure and ultrasonic cleaner or steamer. Avoid re-polishing or re-cutting of the stone. Color may fade in light or with heat. Clean with warm soapy water and a soft brush or cloth.
Created Sapphire	Powdered sapphire heated to recrystallize. Color induced by lattice diffusion of titanium from an external source. Always heated to improve appearance.	Avoid strong detergents, heat, pressure and ultrasonic cleaner or steamer. Avoid re-polishing or re-cutting of the stone. Color may fade in light or with heat. Clean with warm soapy water and a soft brush or cloth.
Smoky Quartz	Heated to improve appearance and to deepen or lighten color.	Color fades when exposed to heat. Clean with warm soapy water and a soft brush or cloth.
Spinel	None	Clean with warm soapy water and a soft brush or cloth.

Created Spinel	None	Clean with warm soapy water and a soft cloth.
Tanzanite	Usually heated to improve appearance.	Do not use ultrasonic cleaner or steamer. Avoid sudden temperature changes. Clean with a damp cloth or soft brush .
Tiger's Eye	Usually heat treated, dyed or bleached to enhance color.	Avoid harsh chemicals and sudden temperature changes. Clean with a damp cloth or soft brush.
Topaz (All colors)	Usually irradiated and heated to produce color. Some topaz may be coated with a thin film of minerals applied through heat.	Clean with warm soapy water and a soft brush or cloth.
Tourmaline (Pink & Green)	Commonly heated and/or irradiated to improve appearance.	Do not use ultrasonic cleaner or steamer. Avoid sudden temperature changes, steaming, and contact with cosmetics, hair spray, perfume and household chemicals. Clean with a soft brush or cloth.
Created Turquoise	Usually stabilized with plastic to enhance durability. Dyed to enhance color.	Do not use ultrasonic cleaner or steamer. Avoid contact with cosmetics, hair spray, perfume and household chemicals. Clean with a damp cloth or soft brush.
Stabilized Turquoise	Porous turquoise immersed in a glue compound, which is absorbed into the stone to give it strength & stability.	Do not use ultrasonic cleaner or steamer. Avoid contact with cosmetics, hair spray, perfume and household chemicals. Clean with a damp cloth or soft brush
Garnet	None	Clean with warm soapy water and a soft cloth.
Zircon	Usually heat treated to create blue color.	Avoid abrasives, rough handling and exposure to excessive light. Clean with warm soapy water and a soft cloth.

 

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