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UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Commercial / trade name · Natural identity; treatment status unknown
Hezhou Yu
A quartzose jade trade name, “Hezhou Yu”, listed in Table A.1 of Annex A of GB/T 34098-2017. The table puts it in one merged cell with other trade names and does not map it to a single basic name: quartzose jade, quartzite jade, chalcedony, agate or jasper.
The name contains the place name Hezhou; GB/T 34098 does not say whether it implies origin. 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 Hezhou Yu forms and what gives its colourFormation setting, process and timescale; where its colour and optical effects come from, each finding graded and sourced
- Hardness, density and refractive index of Hezhou YuEach value with its source and check date
- Hezhou Yu 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 Hezhou YuThe 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
Hezhou Yu is a locality-based trade name for quartzose jade from Hezhou, Guangxi; its parent material is quartz/chalcedony (SiO2). Quartzose jade can form where silica-rich fluids fill rock cavities cyclically from rim to center to yield banded chalcedony and central macrocrystalline quartz. Notably, chalcedony-type materials on the market are commonly dyed (e.g., quench-crackled dyeing), and a dye such as a copper salt can give chalcedony a blue-green color. Identification of Hezhou Yu must therefore also verify whether it has been treated; the name alone cannot establish formation, treatment, or origin.
Scope: Applies to the origin of the underlying material of the quartzose jade (quartz / chalcedony) referred to by the origin trade name 'Hezhou Yu', and notes the risk of dyeing treatment in chalcedony-type materials; does not constitute an identification conclusion on the treatment status or locality of a specific sample.
Sources G&G Fall 2013 · G&G Spring 2020 · GIA Jade Description
Where it forms
A setting where silica-rich fluids fill rock cavities/fractures (volcanic vesicles, vugs, geodes, etc.)
Sources G&G Fall 2013
How it forms, step by step
Silica-rich fluids penetrate rock cavities.
The fluids fill cyclically from rim to center, forming banded chalcedony.
Macrocrystalline quartz crystallizes at the center, building the quartzose jade body.
(Market risk) Chalcedony-type materials may be dyed, e.g., quench-crackled and dyed with a copper salt to a blue-green color.
Link to appearance
Banding reflects cyclic fluid filling; a blue-green color seen on the market may come from dyeing (e.g., a copper salt) rather than natural origin, so appearance cannot replace identification of material and treatment.
Sources G&G Spring 2020 · GIA Jade Description
Timescale
The sources give no absolute age for Hezhou Yu or its parent material.
Sources G&G Fall 2013 · G&G Spring 2020 · GIA Jade Description
Related base materials
- Quartzose jade (quartz/chalcedony): Hezhou yu is a trade name for quartzose jade named after its origin (Hezhou, Guangxi); the underlying material is quartz/chalcedony (SiO2), not an independent mineral species.
Supporting findings
Quartzose jade can form where silica-rich fluids fill rock cavities cyclically from rim to center, producing banded chalcedony and central macrocrystalline quartz.
Evidence grade AScope: Generic formation of the parent material (quartz/chalcedony); not unique to the name Hezhou Yu.
Causes of colour and optical effects
In chalcedony dyed with copper salts, the blue color is caused by Cu2+ ions.
Evidence grade AScope: Applies to the blue color of dyed chalcedony; not to natural chalcedony color.
Other research findings
Chalcedony-type materials carry a dyeing risk: they may be quench-crackled and dyed with a copper salt, with copper concentrated at the surface as strong evidence of dyeing.
Evidence grade AScope: Applies to dyeing of chalcedony-type materials; does not assert that any Hezhou Yu specimen has been treated.
Hezhou Yu is a locality/trade name and does not constitute an independent mineral or material identity; the word 'jade' has historically been misapplied to many jade-like materials.
Evidence grade BScope: Distinguishes the name from material identity; not specimen identification or provenance.
Sources GIA Jade Description
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- GB/T 34098-2017 and GB/T 16552-2017 are recommended (non-mandatory) national standards whose full text is not freely obtainable; the official free preview does not cover them. This record could not verify their clause text, so it makes no assertion about the specific classification, entry, or table position of this locality trade name in those standards.
- The sources give no absolute age for Hezhou Yu or its parent material.
- Dyeing is a general risk for chalcedony-type materials; the sources do not test a Hezhou Yu specimen, and no specimen's treatment or origin may be asserted on this basis.
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
- Quartzose jade (trade name: Hezhou Yu)
GB/T 34098—2017 Table A.1, §6 b) · CIBJO Gemstone Book 2022 4.2.3.3
Construction or treatment status
Natural identity; treatment status unknown
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
"Hezhou Yu" is a market name rather than a mineral species name; before using it, verify: Trade name rather than a mineralogical species name. Actual material is unverified.
What this means for you
Before buying, check the recommended listing name "Quartzose jade (trade name: Hezhou Yu)" 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
- 2026-09-26
Trade-name ruling
- Trade name rather than a mineralogical species name.
- Actual material is unverified.
- Suggested listing name
- Quartzose jade (trade name: Hezhou Yu)
VerifyNames, standards, technical facts, clauses and sources
Names
Trade and mineralogical namesIn GB/T 34098—2017 Table A.1, Hezhou Yu is a trade name for quartz jade, and the original does not specify a basic name; a quartz jade trade name is not used on its own, and the basic name must first be established by testing, with the note “trade name: Hezhou Yu” added. Recommended listing nameThe suggested listing name is quartz jade (trade name: Hezhou Yu). Table A.1 places Hezhou Yu in a single merged cell with quartzite jade, chalcedony, agate and jasper, and the original does not say which of these it belongs to. Names in four languagesThe four-language names cover Simplified Chinese, Traditional Chinese, English (Hezhou Yu) and Japanese (to be checked). Trade and mineralogical namesThe registered mineralogical name reads: quartz jade sold under the trade name Hezhou Yu (GB/T 34098 Table A.1). Institution usageOn authority wording, the FTC and CIBJO texts have no wording for this name (checked), and GIA and Gem-A are unchecked; bodies without a record show the entry's own English name, Hezhou Yu, which does not represent their position. Japanese namesThe entry's own Japanese name is still to be checked, and the GSJ (Japan) wording for this name is not yet verified by this site.
- GSJ (Japan) formal name
- 賀州玉（待核） (not yet checked for this body — the entry's own Japanese name is shown)
- Trade name listed in the GB/T standard (not used on its own)
- 贺州玉 (GB/T 34098—2017 Table A.1; basic name not specified in the original — identify the material first)
- Mineralogical name
- Quartzose jade sold under the trade name Hezhou Yu (GB/T 34098 Table A.1)
Four-language names
- 简体中文
- 贺州玉
- 繁體中文
- 賀州玉
- English
- Hezhou Yu
- 日本語
- 賀州玉（待核）
GB/T 34098 trade names
- Position in Table A.1
- 贺州玉 Hezhou Yu sits in the cell shared by quartzite jade, chalcedony, agate and jasper; the original does not say which one
- How to name it
- The original gives no basic name: identify the material first, then add the note “trade name: 贺州玉 Hezhou Yu”
The full table and naming rule are on the Quartzose Jade page.
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Quartz and chalcedony materials
- Identity tier
- Commercial / trade name
- Mineral chemical class
- Silicates
- Construction or treatment status
- Natural identity; treatment status unknown
What it is and how it's identified
The registered material facts for Hezhou Yu are Mohs hardness 6–7, density 2.53–2.72 g/cm³ and refractive index 1.53–1.55, all from GB/T 34098—2017, where the cited clause is written for quartzose jade (the whole class), not measured for Hezhou Yu alone. GB/T 34098—2017 also notes that the Mohs hardness of quartzose jade is sometimes below 6–7, down to 5.5, and that its density sometimes falls outside 2.53–2.72 g/cm³, down to 2.48 g/cm³ or up to 2.95 g/cm³. This site notes that hardness alone does not support any everyday wearing advice, and that the recorded values are main ranges, not thresholds for establishing the identity of the material. Whole-class features such as chemical composition are likewise given in the cited clause for quartzose jade (the whole class); see the Quartzose Jade entry.
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: these whole-class features are given in the cited clause for quartzose jade (the whole class), so they are not repeated on the Hezhou Yu page; see the material facts on the Quartzose Jade entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Hezhou Yu (how to read class-level values).
Durability
Hezhou Yu — Mohs hardness: 6–7
GB/T 34098—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
- quartzose jade (the whole class)
- Qualification
GB/T 34098-2017 §3.1 notes that hardness may sometimes fall to 5.5. Hardness alone does not support any everyday-wear advice.
Source & check 2026-09-26
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Hezhou Yu — density: 2.53–2.72 g/cm³
GB/T 34098—2017
- Does this standard apply
- applies to this entry
- What this covers
- quartzose jade (the whole class)
- Qualification
GB/T 34098-2017 §3.1 notes that values may sometimes fall to 2.48 or rise to 2.95 g/cm³. The registered range is the main range, not a cut-off for identifying the material.
Source & check 2026-09-26
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Hezhou Yu — refractive index: 1.53–1.55
GB/T 34098—2017
- Does this standard apply
- applies to this entry
- What this covers
- quartzose jade (the whole class)
Source & check 2026-09-26
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (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): 1.54 / 2.62; Closest values: 1Charoite 1.554 / 2.66, 2Changhua Stone 1.56 / 2.6, 3Balin Stone 1.56 / 2.55, 4Shoushan Stone 1.56 / 2.7, 5Bamboo Coral 1.57 / 2.65
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
Evidence and sources
Authority basis and clause sources
Sources
- CIBJO – The World Jewellery Confederation. Gemmological Laboratories Book (Blue Book), Gemmological Commission 2024-1.
- CIBJO – The World Jewellery Confederation. The Gemstone Book (Blue Book), 2022.
- AQSIQ / SAC (China). GB/T 34098—2017 Quartzose jade — Classification and nomenclature.
- SAMR / SAC (China). GB/T 16552—2017 Gems — Nomenclature.
- eCFR (United States). 16 CFR Part 23 — Guides for the Jewelry, Precious Metals, and Pewter Industries.
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 Quartz on this site: 74 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Hezhou Yu) is marked.
- Quartz
Sub-entries (57)
- Agate
Sub-entries (1)
- Amethyst
- Ametrine
- Aventurine Quartz
- Aventurine Quartz / Green Aventurine
- Banded Agate
- Black Agate
- Bloodstone / Heliotrope
- Blue Lace Agate
- Carnelian
- Chalcedony
Sub-entries (2)
- Chrysoprase
- Citrine
- Clear Quartz / Rock Crystal
- Coated Quartz
- Colourless to White Quartz (brand name: Azeztulite)
- Crazy Lace Agate
- Dendritic Agate
- Dyed Agate (Treated: dyed)
- Elestial Quartz / Skeletal Quartz
- Eye Agate
- Flower Agate / Cherry Blossom Agate
- Green Quartz
- High-clarity quartz with golden needle-like inclusions
- Included Quartz
- Jasper
Sub-entries (1)
- Madeira Citrine
- Malachite Agate
- Morion / very dark Smoky Quartz
- Moss Agate
- Moss Chalcedony
- Multi-inclusion Quartz
- Onyx (banded chalcedony)
- Phantom Quartz
- Prase
- Prasiolite / Green Quartz
- Quartz Cat’s-eye
- Quartz claimed to be from the Himalayas
- Quartz Crystal
- Quartz with dark needle-like inclusions
- Quartz with fine fibrous inclusions
- Quartz with flower-like inclusions
- Quartz with golden needle-like inclusions
- Quartz with green needle-like inclusions
- Quartzite Jade
- Quartzose Jade
Sub-entries (9)
- Red Agate
- Rock Crystal
- Rose Quartz
- Rutilated Quartz
- Sard
- Sardonyx
- Silicified Asbestos
Sub-entries (2)
- Hawk’s Eye
- Tiger’s Eye
Sub-entries (1)
- Smoky Quartz
- Smoky Quartz (brown variety)
- Strawberry Quartz
- Yellow-green Quartz
- Agate
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Quartz and chalcedony materials | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Hezhou Yu 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.