Dyed

Naming rule

Naming rule

Dyed [material name]

Market differences and mutual recognition

Chalcedony is the exception in GB/T 16552: there, dyed chalcedony is classed as an optimization, whereas dye in anything else makes it a treatment. In CIBJO's chart the “sugar/acid” darkening process shares code D and the buyer-facing word “Dyed”.

Gem treatments compares how every treatment on this site is named and what each must disclose.

Where the treatment acts (schematic)

Introduces a colouring agent (organic dye or inorganic pigment) into porous, fissured or loosely structured material.

How the naming authorities record it

Materials on which it is recorded

• Agate
• Chalcedony
• Fei Cui / Jadeite Jade
• Turquoise
• Coral
• Marble
• Quartzite Jade
• Jasper

How lab reports word it, by material

The standard report wording (LMHC) for this treatment is set out on these entries and sections:

• Fei Cui / Jadeite Jade
• Nephrite
• Emerald
• Organic fillers in other gemstones

The laboratory testing page's LMHC index lists every LMHC information sheet on report wording.

Care after this treatment

The CIBJO Gemstone Book §6.2 names this treatment in its special care: special-care code k.

CIBJO definitions

Dyeing

application of a dye or stain to natural materials (5.53) or artificial products (5.3) to alter their colour. See clause 4.2.5.2.

CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §5.27, p.23

application of a dye or stain to natural materials (5.68) or artificial products (5.5) to alter their colour.

CIBJO Blue Book — Coral Book (Coral Commission 2024) (CIBJO): §5.36, p.14

The books word this differently; each wording is given with its source.

Dyed/Dyeing

application of a dye or stain to natural materials or artificial products to alter their colour.

CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) (CIBJO): §5.63, p.28

Definitions are quoted verbatim from the cited CIBJO Blue Book; […] marks an excerpt, and the full definition is at the cited clause.

Materials listed for this method in GB/T 16552-2017 Table B.1

JJA/AGL table entries relating to this treatment

Other treatments

• Heated / Heat-treated
• Filled / Fracture-filled
• Diffusion-treated
• Irradiated
• Bleached
• Coated
• HPHT treated
• Laser-drilled
• Waxed
• Impregnated

Sources

What the eye can and cannot tell

Colour on a blue or pink agate bead is more likely dyed than not, since the great majority of blue, green, pink and purple agate on the market is dyed, and CIBJO’s tables state that black onyx is always dyed and black-and-white onyx usually is. Fading and bleeding show up later in wear, which is why dye durability has to be communicated at the point of sale; under Chinese trade practice dyed jadeite is B/C jade.

What to ask for on the report

Dyeing sits on the treatment side of GB/T 16552 Table 1, with a remark that for chalcedony the method counts as optimization instead. Treatment goods are represented under §5.4.2.2 b), the clause recorded here, where the name must carry the treatment method or the word treated; here that gives Dyed [material name].

For jadeite the question is treatment status, dyed goods being B/C jade.

Before you buy: what to check

Work through these in order before paying. None of them replaces a laboratory report; they decide whether you need one.

1. Colour on a blue or pink agate bead is more likely dyed than not, since the great majority of blue, green, pink and purple agate on the market is dyed, and CIBJO’s tables state that black onyx is always dyed and black-and-white onyx usually is. Fading and bleeding show up later in wear, which is why dye durability has to be communicated at the point of sale; under Chinese trade practice dyed jadeite is B/C jade.

2. Dyeing sits on the treatment side of GB/T 16552 Table 1, with a remark that for chalcedony the method counts as optimization instead. Treatment goods are represented under §5.4.2.2 b), the clause recorded here, where the name must carry the treatment method or the word treated; here that gives Dyed [material name].

   For jadeite the question is treatment status, dyed goods being B/C jade.

3. Must be disclosed. Dye may fade, bleed or dissolve in solvents (alcohol, acetone), and dyed material must not be labelled "natural colour"; dyed jadeite counts as B/C jade and must be conspicuously labelled; dyed agate and chalcedony are extremely common.

Questions about this treatment?

Disclosure practice for this treatment differs between authorities and markets, and a report does not always say what was done.

Ask about this treatment in the community forum