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Natural inorganic gem materials · Commercial / trade name · Natural identity; treatment status unknown
Huanglong Yu
A quartzose jade trade name, “Huanglong 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.
Huanglong Yu is listed first in the table. 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 Huanglong Yu forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- Caring for and wearing Huanglong YuDurability indicators and wearing advice
- Hardness, density and refractive index of Huanglong YuEach value with its source and check date
- Huanglong 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?
- Name origin and history of Huanglong YuWhere the name comes from
- Listing and disclosing Huanglong 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
Huanglong Yu is a trade name for a quartz-dominant jade, whose underlying materials are quartz and cryptocrystalline chalcedony. Quartz crystals commonly fill vugs or fissures in volcanic rocks, precipitating slowly from silica-rich fluids, while chalcedony forms as fibrous microcrystals deposited in layers from the void rim inward, producing banding. Its underlying quartz material therefore forms via hydrothermal precipitation and secondary enrichment; the trade name itself carries no independent genesis.
Scope: Applies to describing the origin of the underlying quartz / chalcedony material of Huanglong Yu; the trade name itself does not constitute an independent mineralogical entity.
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Where it forms
Low-temperature silica-rich fluid environments in volcanic vugs, fissures, and hydrothermal veins
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Quartz precipitation environments in hydrothermal veins and in granites and granite pegmatites
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
How it forms, step by step
Silica-rich fluids enter vugs or fissures in volcanic rock.
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Quartz slowly precipitates from solution and crystallizes into druses.
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Chalcedony deposits as fibrous microcrystals in layers from the void rim inward, producing banding.
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Silica further densifies under secondary enrichment and supergene conditions, forming a massive material usable as jade rough.
Sources G&G Spring 2017 · G&G Spring 1982 · G&G Fall 2013 +1
- Causes of Iridescence in Natural Quartz (Gems & Gemology, Spring 2017, Vol. 53, No. 1, Lin & Heaney)
- The Natural Formation and Occurrence of Green Quartz (Gems & Gemology, Spring 1982, Vol. 18, No. 1)
- Agates from Morocco: Gemological Characteristics and Proposed Origin (Gems & Gemology, Fall 2013, Vol. 49, No. 3)
- Quartz
Link to appearance
The appearance of the underlying material depends on quartz/chalcedony grain size and chromophores: coarse quartz may form transparent druses, fibrous microcrystalline chalcedony is semitranslucent with a waxy to greasy luster, and Fe and other elements produce yellow/red warm hues with bands and patterns.
Sources Handbook of Mineralogy
Timescale
The source states that crystallization of comparable silica chalcedony (agate) can last millions of years and proceed in stages.
Sources G&G Fall 2013
Related base materials
- Quartz-dominant jade (quartz-family category): Huanglong yu is a trade name within the category of quartzose jade
- Quartz / chalcedony: Underlying mineral material, mainly quartz and cryptocrystalline chalcedony
Supporting findings
The underlying quartz commonly fills vugs or fissures in volcanic rocks, crystallizing by slow precipitation from silica-rich fluids.
Evidence grade AScope: Applies to the genesis of the underlying quartz crystals; not site-specific.
The underlying chalcedony/agate precipitates as cryptocrystalline silica in stages from the void rim inward, producing banded textures.
Evidence grade AScope: Describes cryptocrystalline chalcedony precipitation, not a single locality.
The underlying quartz material occurs in hydrothermal veins, granites, and granite pegmatites, as well as in sandstones, quartzites, and other rock types.
Evidence grade BScope: Describes occurrence environments; not limited to one locality.
Sources Handbook of Mineralogy
According to the source, crystallization of comparable silica chalcedony can last millions of years and proceed in stages.
Evidence grade AScope: Timescale derives from a specific agate locality; extrapolation to this trade-name material should be cautious.
Recorded localities
Authoritative sources name a single or principal locality.
Asia
- Longling County, Baoshan, Yunnan, ChinaThe provincial standard defines the name by Longling County
Sources DB53/T 440-2012
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 the origin determination guide and the overview of recorded localities.
Where the name comes from
The origin of the trade name "Huanglong Yu" itself is not given in the cited sources. The etymology below belongs to the underlying mineral quartz: its name is of obscure origin in the Middle Ages, first applied to gangue in Saxony, Germany. This etymology belongs to the underlying mineral, not to the name "Huanglong Yu" itself.
Evidence grade BScope: The etymology explains only the origin of the name; it does not establish the material's composition, locality, naturalness, or treatment.
Sources Handbook of Mineralogy
Other research findings
The underlying materials of Huanglong Yu are quartz and cryptocrystalline chalcedony, chemically dominated by SiO2.
Evidence grade BScope: A mineralogical composition statement, not a specific sample identification.
Sources Handbook of Mineralogy
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- 'Huanglong Yu' is a trade name for a quartz-dominant jade, not an independent mineral species or material; this record documents the genesis of its underlying quartz/chalcedony material.
- The full text of GB/T 34098-2017 and GB/T 16552-2017 is not freely obtainable (the free national-standard preview covers only mandatory standards), so Table A.1 and other clause wording could not be verified; no clause numbers or classification tables are cited.
- The timescale derives from a specific agate locality, not a universal value for this trade-name material.
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: Huanglong Yu)
GB/T 34098—2017 Table A.1, §6 b)
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
"Huanglong 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: Huanglong 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: Huanglong Yu)
Care and wear
No institutional care guidance is registered for this material yet; below are its durability indicators and general guidance.
Durability and wearing
Numbers in curly braces, such as {111}, are crystallographic face symbols (Miller indices): each marks a set of crystal faces or cleavage planes. They are reproduced as written in the cited source.
Toughness
tough when massive
Cleavage
Cleavage very rarely observable; poor on {1011}, {0111}, {1010} and others; rhombohedral parting
Daily wear
Hardness 7 resists scratching by ordinary metal and grit, and massive material has good toughness, so it is relatively durable for daily wear; however a hard impact can still chip it, and sudden temperature changes should be avoided to prevent cracking.
Care
Warm water with mild soap and a soft brush suffices; rinse and dry with a soft cloth. For dyed, resin-impregnated or fractured treated material, avoid ultrasonic/steam cleaning and acid washes, and avoid prolonged heat or sunlight.
General guidance: LumaLark's general guidance inferred from the material's properties (hardness, toughness, cleavage); not text from the cited source, and not a guarantee for any specific piece.
Scope: This field describes the material's general properties and is not a finished-product durability promise; it gives no warranty of any specific piece's durability or safety, and the durability of treated (filled, dyed, coated) or composite/assembled material must be assessed separately.
VerifyNames, standards, technical facts, clauses and sources
Names
Trade and mineralogical namesHuanglong Yu is a quartzose jade trade name listed in GB/T 34098—2017 Table A.1; it is a commercial/trade name, not a mineralogical species name. GB/T 34098—2017 does not assign Huanglong Yu to any one basic name among quartzite jade, chalcedony, agate and jasper; the original specifies no basic name, so the basic name must be determined from the test results for the sample. Quartzose jade trade names should not be used on their own but must be combined with the basic name, with the note trade name: Huanglong Yu added in the quality document. Recommended listing nameThe suggested listing name is quartzose jade (trade name: Huanglong Yu). Institution usageThe entry's own English name is Huanglong Yu; the FTC and CIBJO texts on file have no wording for this name (checked), and GIA and Gem-A are unchecked; bodies without a recorded wording show the entry's own English name, which does not represent their position. Japanese namesThe entry's own Japanese name is marked pending verification, and the wording of Japan's GSJ for this name is not yet verified by this site. Names in four languagesFour-language names are given in Simplified Chinese, Traditional Chinese, English (Huanglong Yu) and Japanese (pending verification).
- GSJ (Japan) formal name
- 黄龍玉（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)
- 黄龙玉 (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 Huanglong Yu (GB/T 34098 Table A.1)
Four-language names
- 简体中文
- 黄龙玉
- 繁體中文
- 黃龍玉
- English
- Huanglong Yu
- 日本語
- 黄龍玉（待核）
GB/T 34098 trade names
- Position in Table A.1
- 黄龙玉 Huanglong 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: 黄龙玉 Huanglong 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 Huanglong Yu take values for quartzose jade as a whole class: chemical composition is registered for the whole class (see the Quartzose Jade entry); Mohs hardness 6–7, density 2.53–2.72 g/cm³ and refractive index 1.53–1.55 are all registered for quartzose jade (the whole class), not measured on Huanglong Yu itself. GB/T 34098—2017 also notes that the Mohs hardness of quartzose jade is sometimes below 6–7, down to 5.5, and its density sometimes falls outside 2.53–2.72 g/cm³, as low as 2.48 g/cm³ or as high as 2.95 g/cm³. This site further notes that hardness alone does not amount to any advice on everyday wear, and that the registered density is the main range, not a threshold for establishing the identity of the material.
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 Huanglong 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 Huanglong Yu (how to read class-level values).
Durability
Huanglong 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
Huanglong 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
Huanglong 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 (Huanglong 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 Huanglong 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.