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GB/T 16552: optimization vs treatment

How GB/T 16552-2017 sorts each method into optimization or treatment: the Table B.1 row first, then the tiers of Table 1 in clause 5.4.1.

How the category is decided

Annex B of GB/T 16552-2017 is normative. Its Table B.1 lists, material by material, the common enhancement and treatment methods, their effect and their category; Table 1 in clause 5.4.1 gives the general rule per method.

Where Table B.1 puts “see 5.4.1” in the category column (filling for 36 materials, coating for 4), there is no single answer: Table 1 grades it by the filler or by the nature of the coating, and the grades are set out in the Filled and Coated rows of “GB/T category by method” below.

The two material exceptions noted under Table 1 (dyeing of chalcedony and irradiation of rock crystal count as optimization) also show on the matching rows of Table B.1. When this site decides whether a method is optimization or treatment for a material, it uses the Table B.1 row first and falls back to Table 1 only when the material has no row.

GB/T category by method

Each treatment process on this site, with how GB/T 16552-2017 categorizes it. Where Table 1 grades a method (filling, coating), the grades are given in the same row.

This table scrolls sideways on narrow screens.

Treatment processGB/T category (this site's summary)
Heated / Heat-treatedOptimization (GB/T 16552-2017 §5.4.1 Table 1: heating is classified as optimization, remark cell empty; representation method at §5.4.2.1).
Filled / Fracture-filled

GB/T 16552-2017 §5.4.1 Table 1: filling has three tiers - colourless oil/wax filling (including minor resin filling of emerald as clarity optimization) is optimization with no remark; glass or synthetic-resin filling of minor fissures and cavities is optimization (annotation required); saturating porous, heavily fissured material with Pb- or Bi-bearing glass or cured synthetic resin is treatment.

Representation method: optimization at §5.4.2.1, treatment at §5.4.2.2 - the name must carry the treatment method or the word “treated” before or after it; the standard does not require the filler substance to be named.

Diffusion-treatedTreatment (GB/T 16552-2017 §5.4.1 Table 1: diffusion treatment is classified as treatment, remark cell empty; representation method at §5.4.2.2).
IrradiatedTreatment (GB/T 16552-2017 §5.4.1 Table 1: irradiation is classified as treatment, with the remark that this method is classified as optimization for quartz; representation method at §5.4.2.2).
DyedTreatment (GB/T 16552-2017 §5.4.1 Table 1: dyeing is classified as treatment, with the remark that this method is classified as optimization for chalcedony; representation method at §5.4.2.2).
BleachedOptimization (GB/T 16552-2017 §5.4.1 Table 1: bleaching is classified as optimization, remark cell empty; the combined method “bleaching and filling” is classified as treatment; representation method at §5.4.2.1/§5.4.2.2).
CoatedGB/T 16552-2017 §5.4.1 Table 1: coating has two tiers - a colourless film on the surface of a natural organic gem is optimization (annotation required); a colourless or coloured film on a natural gemstone or jade is treatment. Representation method: optimization at §5.4.2.1, treatment at §5.4.2.2 (see Table 1).
HPHT treatedTreatment (GB/T 16552-2017 §5.4.1 Table 1: high-pressure high-temperature treatment is classified as treatment, remark cell empty; representation method at §5.4.2.2).
Laser-drilledTreatment (GB/T 16552-2017 §5.4.1 Table 1: laser drilling is classified as treatment, remark cell empty; representation method at §5.4.2.2).
WaxedOptimization (GB/T 16552-2017 §5.4.1 Table 1: filling with colourless oil or wax is classified as optimization; the standard has no separate entry for surface waxing, and wax appears only in its definition of filling; representation method at §5.4.2.1).
Impregnated

Graded (GB/T 16552-2017 has no separate entry for impregnation; its §3.4.6 gives “filling or impregnation” as the English term for filling, so this site classes impregnation by the impregnating material under the three filling tiers of §5.4.1 Table 1: filling with colourless oil or wax, or filling fissures with a small amount of resin to improve the appearance slightly, is optimization — for emerald this counts as clarity optimization and is optimization (annotation required); glass or synthetic-resin filling of minor fissures and cavities is optimization (annotation required); saturating porous, heavily fissured material with Pb- or Bi-bearing glass or cured synthetic resin is treatment; the combined method “bleaching and filling” is also treatment.

Turquoise: in Annex B Table B.1 its “filling” row likewise says “see 5.4.1”, and a separate “density optimization” row (improving durability and appearance) is optimization (annotation required) — turquoise impregnation that is density optimization falls in that tier, the rest follows the three tiers above.

Representation method: optimization at §5.4.2.1, treatment at §5.4.2.2).

GB/T 16552-2017, Annex B, Table B.1

Below are all 52 rows of Table B.1 (printed page in brackets); each row name links to this site’s entry for that material, where the row’s methods, effects and categories are shown.