On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Mineral / gemstone variety · Natural identity; treatment status unknown
Hetian Yu, Brown Sugar-coloured Nephrite Variety
Also known asbrown nephrite (conditional name)
Brown to yellowish-brown Nephrite classed as a Hetian Yu variety in the Chinese naming system; the name does not prove origin in Hetian, Xinjiang. This page compares how the major standards and institutions name it, what must be disclosed when selling it, whether it can be worn every day, how it is treated and identified, and which source each conclusion comes from.
Price, rarity and origin are outside the scope of this wiki.
What this page can answer
This page covers
- How Hetian Yu, Brown Sugar-coloured Nephrite Variety forms and what gives its colourFormation setting, process and timescale; where its colour and optical effects come from, each finding graded and sourced
- How to identify Hetian Yu, Brown Sugar-coloured Nephrite VarietyHow far lab testing can go
- Treatments and enhancements of Hetian Yu, Brown Sugar-coloured Nephrite VarietyThe enhancements and treatments the GB/T and JJA/AGL tables list
- Caring for and wearing Hetian Yu, Brown Sugar-coloured Nephrite VarietyCleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Hetian Yu, Brown Sugar-coloured Nephrite VarietyEach value with its source and check date
- Hetian Yu, Brown Sugar-coloured Nephrite Variety in English, Chinese and Japanese; national standard namesNames in four languages, the GB/T standard name and the suggested listing name; and: Has any of GIA, FTC, CIBJO or Gem-A put a name for it on record here?
- Listing and disclosing Hetian Yu, Brown Sugar-coloured Nephrite VarietyThe listing name to use; what must be disclosed before sale
What we cannot conclude
- Whether one particular bead is natural, treated or synthetic — only a laboratory report can settle that.
- Geographic origin, unless an origin report accompanies the item.
- Price, rarity or investment value: this wiki covers naming and disclosure only.
Material research: formation, causes and history
What authoritative sources say about how this material forms, what causes its colour and optical effects, where its name comes from and how people have used it. Each statement carries an evidence grade and its sources; it describes the material in general, not any specific piece.
How it forms
Under Chinese nomenclature Hetian tangyu denotes brown to yellow-brown nephrite presented under the Hetian Yu name, whose material basis is a fine-grained fibrous aggregate of tremolite-actinolite series amphibole of metamorphic origin, formed chiefly by metasomatism: silica-rich fluids replacing dolomite-rich rocks or calcium-rich fluids reacting with serpentinites. The sugar colour is often a skin or banded colour, but its specific cause is not given in the cited sources. It is not an independent mineral species; 'Hetian' carries an origin sense and the name alone is not an origin determination.
Scope: Applies to a material-level description of the origin of 'Hetian Yu, brown sugar-coloured nephrite variety' as a trade / variety name for brown nephrite; the name is not taken as a producing area or as an identification conclusion for a specific sample.
Sources G&G Summer 2023 · GIA Jade Description
Where it forms
Contact-metamorphic setting: Ca-Mg siliceous sediments heated by an igneous body.
Sources G&G Summer 2023
Regional metamorphism / greenschist facies: low-grade metamorphism of ultramafic or magnesium-carbonate rocks.
Sources G&G Summer 2023
Hydrothermal metasomatic (hydrothermal-metamorphic) setting: silica-rich fluids replacing dolomite-rich rocks, or calcium-rich fluids reacting with serpentinites.
Sources G&G Summer 2023
How it forms, step by step
Protolith in place: dolomite-rich / magnesium-carbonate rock or ultramafic rock exists in contact with an igneous body or fluid system.
Fluid metasomatism: silica-rich fluid enters dolomitic rock, or calcium-rich fluid reacts with serpentinite (metasomatism).
Tremolite-actinolite crystallises: amphibole forms via the reaction 5 dolomite + 8 aqueous silica + water → tremolite + 3 calcite + 7 aqueous carbon dioxide.
Fibrous interlocking (felted) aggregate develops: fine fibrous crystals interlock into a dense, tough jade.
Link to appearance
The fine interlocking fibrous texture makes nephrite exceptionally tough and carvable and gives its translucent-to-opaque, waxy look; colour varies with composition and iron content, generally more muted than jadeite.
Sources G&G Summer 2023 · GIA Jade Description
Timescale
The available sources give no absolute geological age or date for nephrite formation.
Sources G&G Summer 2023 · GIA Jade Description
Related base materials
- Nephrite: Parent material of Hetian sugar-coloured nephrite; brown nephrite marketed under the name Hetian yu
Supporting findings
Nephrite forms through hydrothermal metamorphism (metasomatism): either silica-rich fluids move into dolomite-rich rocks, or calcium-rich fluids react with serpentinites; the dolomite path can be written 5 dolomite + 8 aqueous silica + water --> tremolite + 3 calcite + 7 aqueous carbon dioxide.
Evidence grade AScope: Describes the natural genesis of the underlying material (tremolite-actinolite nephrite) only; it does not establish a specimen's origin, treatment, or colour subcategory.
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Asia
- Qiemo County, Bayingolin, Xinjiang, ChinaThe source mentions Qiemo sugar nephrite only in a cited reference title
Sources Minerals (Fang et al., 2024)
These are localities recorded by authoritative sources, not an origin finding for any individual piece. The CIBJO Gemstone Book (2022, §4.2.3) says a place of origin names where a gem was mined or harvested, is a matter of opinion, does not imply a level of quality, and that cutting, processing or exporting centres must not be used to imply origin. See how far testing can go on this page, the origin determination guide and the overview of recorded localities.
Causes of colour and optical effects
Hetian tangyu denotes brown to yellow-brown (sugar-coloured) nephrite presented under the Hetian Yu name; the sugar colour is often a skin or banded colour. Its specific cause (whether iron-oxide staining or supergene/secondary oxidation) is not given in the cited sources and requires testing; none is asserted.
Evidence grade BScope: Describes the sugar colour's appearance only; no cause is asserted (the sources do not give one).
Sources GIA Jade Description
Other research findings
Nephrite is a fibrous (interlocking/felted) aggregate; the amphibole it is mostly built from belongs to the tremolite-actinolite series, whose compositional range runs from the tremolite end member Ca2Mg5Si8O22(OH)2 to the ferro-actinolite end member Ca2Fe5Si8O22(OH)2. It is thus not a single crystal.
Evidence grade AScope: Describes nephrite's mineral composition range only; it does not establish a specimen's origin, treatment, or colour.
This name is a colour/variety trade name under the Chinese nephrite system, denoting a tremolite-actinolite material; without the full text of the relevant standard this record makes no clause-level definition of its colour boundary and does not treat it as an independent mineral species.
Evidence grade BScope: 'Hetian' and 'tang' here are name/origin senses and a brown-nephrite colour name, not an origin determination; no GB/T clauses are invented.
Sources GIA Jade Description
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The full text of GB/T 16552 and similar standards is not obtainable, so the clause-level basis of this variety name could not be verified; no clauses or tables are invented.
- 'Hetian' is an origin-laden name; the name alone cannot prove origin or a specimen.
- The cause of the sugar colour is not given in the available sources and requires testing; none is asserted.
Methodology
- Origin determination and its limits
- Quality grading and value factors
- How gemmology became a technical discipline
Evidence grades
- A
- Standards bodies, government geological surveys, peer-reviewed research and museum records
- B
- Institutional educational material
- C
- Specialist databases or cautious readings
A statement is never graded above its strongest source.
This section is LumaLark's own factual restatement of public authoritative sources, credited item by item; it contains no verbatim excerpts, images or third-party logos.
DecideListing name, disclosure, care and treatments
- Suggested listing name
- Hetian Yu, brown sugar-coloured nephrite variety (geographic origin requires separate evidence)
GB/T 16552—2017 5.1.1 c)
Construction or treatment status
Natural identity; treatment status unknown
Treatments recorded for this material: Filled / Fracture-filled (via parent material), Dyed (via parent material)
Related:Disclosure and cautions
This page cannot answer
Natural? · Origin · Price
A lab report settles these; this wiki covers naming and disclosure.
Related:What this page can answer
Answer at a glance
The Chinese standard lists Hetian Yu, Brown Sugar-coloured Nephrite Variety under a different Chinese name from its common trade name (GB/T 16552—2017 Table A.2); use "Hetian Yu, brown sugar-coloured nephrite variety (geographic origin requires separate evidence)" for listings.
What this means for you
Before buying, check the recommended listing name "Hetian Yu, brown sugar-coloured nephrite variety (geographic origin requires separate evidence)" and any disclosed treatments on this page, and ask the seller for a grading report if in doubt.
Known uncertainty
- This entry's exact material identity is not fully settled.
- See “Disclosure and cautions” above
- Last reviewed
- 2026-09-01
Trade-name ruling
- Laboratory identification required before the name is used.
- Suggested listing name
- Hetian Yu, brown sugar-coloured nephrite variety (geographic origin requires separate evidence)
Care and wear
The item-by-item care advice that the GIA Care and Cleaning Guide gives for the whole class, and so for Hetian Yu, Brown Sugar-coloured Nephrite Variety, is set out in full under care on the Nephrite entry.
Care
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Treatments and identification leads
One row per treatment, with three standards side by side: how often it occurs and how stable it is (CIBJO), its category in GB/T 16552—2017 Table B.1 (this site's paraphrase) and how the JJA/AGL 2025 table lists it. Each CIBJO value links to its entry under “Testing and market”, where the wording and source are given in full.
This table scrolls sideways on narrow screens.
| Treatment | Market frequency (CIBJO) | Stability (CIBJO) | GB/T 16552 category | JJA/AGL listing | Identification leads |
|---|---|---|---|---|---|
| Filling | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Dyeing | — | — | Treatment | — | — |
“—” means the cited source gives no value for that item, not “none”. Source: GB/T 16552—2017 Table B.1 (row for Nephrite)
Whether a treatment has to show in the name differs between the two rule sets (this site’s paraphrase):
- GB/T 16552—2017: a method classed as treatment has to be stated in the name itself — the method put before the name, or added in brackets after it; a method classed as optimization does not need to appear in the name, though one marked “Optimization (annotation required)” still has to be noted in the quality documents. Source: §5.4.2.1 a), b); §5.4.2.2 a)
- CIBJO Gemstone Book 2022: no longer splits treatments into ones that need specific disclosure and ones that need only general disclosure: every treatment is to be disclosed, and the seller tells the buyer which treatment was used and what special care it calls for. Source: §4.2.5 Note 2, §4.2.5.1, pp.14–15
What this table covers
What this page can give
- Registered treatments, their stability and how often they occur (see the table above)
- Identification leads for each treatment, for use when sending a stone for testing
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Hetian Yu, Brown Sugar-coloured Nephrite Variety, the name register records "brown nephrite", for which no restriction on use as a name is recorded; one further name in a non-Latin script is listed in the name register below (1 with no restriction recorded on use as a name).
Chinese standard nameThe Chinese formal name for Hetian Yu, Brown Sugar-coloured Nephrite Variety is "Tang Yu" (sugar jade), from GB/T 16552—2017 Table A.2. Trade and mineralogical namesMarket names include Tang Yu (Hetian Yu). Candidate search termsTrade names/synonyms also include brown nephrite, which in the name register is a search candidate only. Recommended listing nameThe suggested listing name is Hetian sugar jade (nephrite; origin to be separately proven). Names in four languagesNames are given in Simplified Chinese, Traditional Chinese, English (Hetian Yu, Brown Sugar-coloured Nephrite Variety) and Japanese. The Japanese name is the entry's own, and the wording used by GSJ (Japan) for it is not yet verified by this site. Institution usageThe English name Hetian Yu, Brown Sugar-coloured Nephrite Variety is the entry's own English name; the wording of GIA, FTC, CIBJO and Gem-A for Hetian Yu, Brown Sugar-coloured Nephrite Variety is not yet verified by this site, and the name does not represent the position of GIA, FTC, CIBJO or Gem-A.
Name register
Every name recorded for this entry, with how it is classified, whether it may be matched to this entry automatically, whether it may be used as a product name, and the clause it rests on.
This table scrolls sideways on narrow screens.
| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (2) | ||||
| brown nephriteEnglish | narrower name (variety or subtype) | search candidate only | no restriction recorded | editorial ruling (no clause cited) |
| 糖玉（和田玉）Simplified Chinese | market name | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- 和田玉（糖玉）／褐色ネフライト (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 糖玉 (GB/T 16552—2017 Table A.2)
- Mineralogical name
- Brown to yellow-brown nephrite material named as a Hetian Yu variety under Chinese nomenclature
- Trade names and synonyms
- brown nephrite (narrower name (variety or subtype); conditional name)
Four-language names
- 简体中文
- 和田糖玉
- 繁體中文
- 和田糖玉
- English
- Hetian Yu, Brown Sugar-coloured Nephrite Variety
- 日本語
- 和田玉（糖玉）／褐色ネフライト
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Jade materials
- Identity tier
- Mineral / gemstone variety
- Mineral chemical class
- Silicates
- Construction or treatment status
- Natural identity; treatment status unknown
Treatments listed by standards
GB/T Table B.1Hetian Yu, Brown Sugar-coloured Nephrite Variety is classified under GB/T 16552—2017 Annex B Table B.1 by applying the content of the nephrite row of Table B.1. The nephrite row of Table B.1 lists filling as graded and places dyeing in the treatment category. See alsoThe notes to Table B.1 and the definitions of the filling grades are on this site's treatments page; the full content, including the effect column, is in the nephrite entry.
GB/T 16552-2017, Annex B, Table B.1
Under the “Nephrite” row of Table B.1: Filling Graded — see §5.4.1, Table 1; Dyeing Treatment. The full row, with the effect column, is on the Nephrite page.
What Table B.1 is, and how the “see 5.4.1” grades are defined: see the GB/T 16552: optimization vs treatment page.
What it is and how it's identified
Registered material facts
Each row carries its own source and check date and can be cited on its own; “—” means the cited source gives no value, not “none”.
Chemical composition, luminescence, UV-visible spectrum, infrared spectrum, magnification: these whole-class features are given in the cited clause for nephrite as a whole (not one source), so they are not repeated on the Hetian Yu, Brown Sugar-coloured Nephrite Variety page; see the material facts on the Nephrite entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Hetian Yu, Brown Sugar-coloured Nephrite Variety (how to read class-level values).
Structure
Hetian Yu, Brown Sugar-coloured Nephrite Variety — structure (overall): a crystalline aggregate that is often fibrous
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Hetian Yu, Brown Sugar-coloured Nephrite Variety — Mohs hardness: 6–6.5
GB/T 16553—2017
Reference points on this site: Talc 1–3, Fluorite 4, Apatite 5–5.5, Orthoclase 6–6.5, Topaz 8, Diamond 10 (Source: GB/T 16553—2017); Gypsum 1.5–2, Calcite 3, Quartz 7 (Source: Handbook of Mineralogy); Corundum 9 (Source: GIA Gem Encyclopedia (care guide))
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — cleavage: Tremolite crystals cleave perfectly in two directions; aggregates usually have no cleavage.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Hetian Yu, Brown Sugar-coloured Nephrite Variety — density: 2.9–3.1 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
- Qualification
The clause we cite gives 2.95, with a stated tolerance of +0.15 / -0.05. The range shown here is worked out from that.
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Hetian Yu, Brown Sugar-coloured Nephrite Variety — optic character: anisotropic aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — refractive index: 1.6–1.641
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
- Qualification
The clause we cite gives 1.606–1.632, with a stated tolerance of +0.009 / -0.006. The range shown here is worked out from that.
- General note
- the clause has finer ranges
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — birefringence: not measurable on an aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — pleochroism: not measurable on an aggregate
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — optical effect (chatoyancy): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Hetian Yu, Brown Sugar-coloured Nephrite Variety — body colour: brown to yellowish brown
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- Qualification
In chapter 5 of GB/T 16553—2017, the colour entries of Peridot, Epidote, Sinhalite and other variety clauses also name brown or a brownish colour.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 Colour · Brown nephrite (tangyu) (locator checked 2026-09-28)
- Fact checked on
- 2026-09-26
- CIBJO definitions
- chatoyancy
Quality factors
Hetian Yu, Brown Sugar-coloured Nephrite Variety — quality factor (lustre): vitreous to greasy
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- nephrite as a whole (not one source)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
This material (RI / SG midpoints): 1.621 / 3; Closest values: 1Danburite 1.633 / 3, 2Amblygonite 1.607 / 3.02, 3Dushan Yu / Dushan Jade 1.63 / 2.9, 4Prehnite 1.625 / 2.88, 5Lazulite 1.627 / 3.12
Show the full chart (330 registered materials)
Outside the full chart's range, drawn as triangles at the edge (RI / SG midpoints): Hematite 3.045/5.12, Synthetic Rutile 2.76/4.26, Rutile 2.753/4.23, Synthetic Moissanite 2.67/3.22
Testing and market
The CIBJO laboratory protocol covers Hetian Yu, Brown Sugar-coloured Nephrite Variety under “Nephrite” (§6.1.54): see identification on the Nephrite entry; the required tests are listed on the CIBJO laboratory protocol table for Nephrite.
How far testing can go
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Evidence and sources
Authority basis and clause sources
Sources
Further reading
Related entries and topic cluster
Parent entry and related pages on this site. Rows marked “Planned” are suggested new content and have no link yet.
Related-entry tree for Tremolite on this site: 6 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Hetian Yu, Brown Sugar-coloured Nephrite Variety) is marked.
- Tremolite
Sub-entries (2)
- Hetian Yu / Nephrite
Sub-entries (2)
- Hetian Yu, Brown Sugar-coloured Nephrite Variety
- Hetian Yu, Green Nephrite Variety
- Nephrite
Sub-entries (1)
- Hetian Yu / Nephrite
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Jade materials | Live |
| Treatments recorded for this material | Filled / Fracture-filled (via parent material), Dyed (via parent material) | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Hetian Yu, Brown Sugar-coloured Nephrite Variety entry are maintained by the LumaLark wiki and matched one by one to the standard clauses or institutional sources they cite: every fact carries its source (with a clause or page locator) and a check date, so it can be traced back to the original. The entry exists so that buyers and sellers can check naming, disclosure and material facts item by item.