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UnderstandWhat it is, what people ask, how far this page goes
Unspecified-material term · Trade name: material identity unverified · Actual material to be verified
Nanhong Agate
Also known asNanhong · south red agate (annotation only, never as the product name)
A Chinese commercial name in the agate family. GB/T 34098-2017 Table A.1 lists "Nanhong" and "Nanhong Agate" as quartzose jade trade names without saying which basic name they match; material, origin and treatment all need testing. 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 Nanhong Agate 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 Nanhong AgateIdentification points from the research literature
- Treatments and enhancements of Nanhong AgateThe enhancements and treatments the GB/T and JJA/AGL tables list
- Hardness, density and refractive index of Nanhong AgateEach value with its source and check date
- Nanhong Agate 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 Nanhong AgateThe 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
Nanhong Agate (Chinese trade name; material unverified) is a trade name used in the Chinese market for a quartz-based ('quartz jade')/agate material, also called Nanhong; it is not a mineral species. The substance it denotes is agate, which belongs to the microcrystalline forms of silica and is usually described as banded chalcedony while also carrying several other silica polymorphs - that is, cryptocrystalline quartz (chalcedony/agate). According to the leading hypothesis, the voids inside volcanic rock fill up cyclically, starting at the rim and working toward the middle, as silica-rich fluids pass in through microfissures or infiltration canals; how wide the zones are and what overall pattern results depends on the silica concentration of the fluids together with the temperature, the pressure and when those fluid pulses arrived, whereas Fe, Ti, Mn and other elements influence only the colour of the zones. Agate may be treated - quench-crackled and dyed, for instance - to alter its colour. Note: no definition of the name "Nanhong Agate (Chinese trade name; material unverified)" was found in the authoritative sources consulted (GIA, CIBJO); the term is a trade name and both the material and its origin require identification.
Scope: Applies to the naming boundary of Nanhong agate as a Chinese-market trade name for quartzose jade / agate, and an overview of the formation, composition and treatment of agate; an authoritative definition of the name itself is lacking in the cited sources (flagged as a grade C gap).
Sources G&G Fall 2013 · CIBJO Gemstone Book 2022 · G&G Summer 2020
Where it forms
Voids/geodes in volcanic rock — a setting where silica-rich fluids fill from the rim to the centre in cycles.
Sources G&G Fall 2013
Agate can occur as lens-shaped or spherical geodes within volcanic rocks such as Triassic basaltoids.
Sources G&G Fall 2013
How it forms, step by step
Silica-rich fluids enter voids in volcanic rock through microfissures or infiltration canals.
Filling proceeds from the rim to the centre in cycles, forming banded chalcedony/silica polymorphs.
Fe, Ti, Mn and other elements colour the zones differently; the material may be further treated, e.g. dyed.
Link to appearance
Agate is characterised by banded silica (chalcedony); the colour of the zones is governed by Fe, Ti, Mn and other elements, while the pattern reflects the filling cycles and fluid conditions.
Sources G&G Fall 2013 · CIBJO Gemstone Book 2022
Timescale
The source gives no absolute timescale for agate formation (though it notes crystallization can last millions of years and proceed in stages).
Sources G&G Fall 2013 · CIBJO Gemstone Book 2022 · G&G Summer 2020
Related base materials
- Chalcedony / agate (cryptocrystalline quartz): The quartzose jade/agate material referred to by this name, composed mainly of cryptocrystalline quartz
Supporting findings
According to the leading hypothesis, the voids inside volcanic rock fill up cyclically, starting at the rim and working toward the middle, as silica-rich fluids pass in through microfissures or infiltration canals; how wide the zones are and what overall pattern results depends on the silica concentration of the fluids together with the temperature, the pressure and when those fluid pulses arrived.
Evidence grade AScope: A hypothesis for banded-chalcedony formation.
Agate can occur as lens-shaped or spherical geodes within volcanic rocks (e.g. Triassic basaltoids).
Evidence grade AScope: A setting example; not locality-specific.
Causes of colour and optical effects
In the fluids, Fe, Ti and Mn and similar elements alter only the colour of the agate's zones.
Evidence grade AScope: A colour-cause statement.
How it is identified
The colour and inclusion appearance of Nanhong agate cannot establish whether a stone is natural, synthetic or treated: quartz varieties that look alike may differ entirely in composition, growth history and treatment, and synthetic and natural quartz share essentially the same composition and physical properties, so the unaided eye cannot separate them. Laboratory identification rests on measurable properties and the division of labour between instruments — a polariscope with a conoscope lens can judge colour-zoning orientation from extinction and optic-axis readings, a refractometer gives refractive-index values, and EDXRF with infrared spectroscopy supplies chemical and structural fingerprints. Limitations: some methods depend on how the stone was cut and on comparison with reference material, and the final conclusion must be issued by an accredited gemological laboratory through testing rather than inferred from appearance.
Evidence grade AScope: Identification and separation points; testing must be performed by an accredited gemological laboratory, and no self-test thresholds are given.
Sources G&G Summer 2014 · CIBJO Gemstone Book 2022
Other research findings
"Nanhong Agate (Chinese trade name; material unverified)" is a Chinese-market trade name for a quartz-based / agate material and is not a mineral species; the material and origin require identification and its basic name must be determined by testing as chalcedony/agate. The authoritative sources consulted (GIA, CIBJO) do not define the name, so it has no authoritative mineralogical definition and does not constitute an identifiable material type.
Evidence grade CScope: Based only on the cited authoritative sources; where they are silent the gap is stated, not filled from commercial sites.
Sources CIBJO Gemstone Book 2022
Agate belongs to the microcrystalline forms of silica and is usually described as banded chalcedony, though it also carries several other silica polymorphs; its principal component is cryptocrystalline quartz (chalcedony/agate).
Evidence grade AScope: Composition/structure of agate.
Sources G&G Fall 2013 · CIBJO Gemstone Book 2022
Chalcedony/agate can be treated, e.g. quench-crackled and dyed, to change colour; the actual treatment status of Nanhong Agate (Chinese trade name; material unverified) requires identification.
Evidence grade AScope: A generally available treatment for chalcedony/agate; it does not mean the material is necessarily treated.
Limits of this research
- Research status: No authoritative source specific to this material was found; findings come from the parent material or are marked as gaps
- The name does not appear in the authoritative sources consulted, so the name itself rests on evidence level C only; this account draws on general sources on agate/chalcedony, not on commercial gem shops or content farms.
- The material and origin of this name require identification.
- No absolute age for agate formation is given by the sources.
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
- Nanhong Agate (use only once identified as agate or chalcedony)
GB/T 16552—2017 5.1.1 c), 5.1.2.1 b) · GB/T 34098—2017 Table A.1, §6 b)
Construction or treatment status
Actual material to be verified
Treatments recorded for this material: Heated / Heat-treated (via parent 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
"Nanhong Agate (Chinese trade name; material unverified)" is a market name rather than a mineral species name; before using it, verify: Trade name rather than a mineralogical species name.
What this means for you
Before buying, check the recommended listing name "Nanhong Agate (use only once identified as agate or chalcedony)" 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
- Trade name rather than a mineralogical species name.
- Suggested listing name
- Nanhong Agate (use only once identified as agate or chalcedony)
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 |
|---|---|---|---|---|---|
| Heating | — | — | Optimization | — | — |
| Filling | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Dyeing | — | — | Optimization | — | — |
“—” means the cited source gives no value for that item, not “none”. Source: GB/T 16552—2017 Table B.1 (row for Chalcedony)
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
VerifyNames, standards, technical facts, clauses and sources
Names
For Nanhong Agate, "Nanhong" is recorded with no restriction on use as a name, while "south red agate" may appear only as an annotation, never as the product name (GB/T 34098—2017 Table A.1; GB/T 34098—2017 §6 b)); 2 further names in non-Latin scripts are listed in the name register below (2 with no restriction recorded on use as a name).
Trade and mineralogical namesNanhong Agate is listed in GB/T 34098—2017 Table A.1 as a trade name for quartzose jade and is not used on its own; the original does not specify the basic name, so the basic name must first be determined by identification, followed by the note "trade name: Nanhong Agate" (or "Nanhong"), and the original also does not specify whether it corresponds to quartzite jade, chalcedony, agate or jasper. Recommended listing nameThe suggested listing name is Nanhong Agate (use after identification as agate/chalcedony). Trade and mineralogical namesIt is also called Nanhong; "agate Nanhong" is a market name that maps to the more specific Nanhong Agate rather than to the broader agate. Names in four languagesNames are given in Simplified Chinese, Traditional Chinese, English (Nanhong Agate, a Chinese trade name with the material not verified) and Japanese (a Chinese market name with the material not identified). Institution usageOn institutional wording, the FTC and CIBJO texts contain no wording for this name (checked), while 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 has its own Japanese name, and the wording used by GSJ (Japan) for it is not yet verified by this site.
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 (3) | ||||
| NanhongEnglish | transliteration | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
| 南红Simplified Chinese | market name | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
| 玛瑙南红Simplified Chinese | market name | matched automatically | no restriction recorded | editorial ruling (no clause cited); Note: Market product name matched to the more specific Nanhong agate entry rather than to agate in general. |
| annotation only, never as the product name (1) | ||||
| south red agateEnglish | market name | matched only once the condition is confirmed | annotation only, never as the product name | GB/T 34098—2017 Table A.1; GB/T 34098—2017 §6 b) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- 南紅瑪瑙（中国市場名・材質未同定） (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)
- 南红玛瑙 (GB/T 34098—2017 Table A.1; basic name not specified in the original — identify the material first)
- Mineralogical name
- Chinese agate-related trade term; actual material, origin and treatment require identification
- Trade names and synonyms
- Nanhong (transliteration) · south red agate (market name; annotation only, never as the product name)
Four-language names
- 简体中文
- 南红玛瑙
- 繁體中文
- 南紅瑪瑙
- English
- Nanhong Agate (Chinese trade name; material unverified)
- 日本語
- 南紅瑪瑙（中国市場名・材質未同定）
Qualifiers stripped from the headline name
GB/T 34098 trade names
- Position in Table A.1
- Both 南红 Nanhong and 南红玛瑙 Nanhong Manao sit 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: 南红玛瑙 Nanhong Manao” (or 南红 Nanhong)
The full table and naming rule are on the Quartzose Jade page.
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Material identity unspecified
- Material domain
- Unspecified-material term
- Browsing family
- Bead-form and unidentified trade terms
- Identity tier
- Trade name: material identity unverified
- Mineral chemical class
- Mixed / composition-dependent
- Construction or treatment status
- Actual material to be verified
Treatments listed by standards
Nanhong Agate is classified under GB/T 16552—2017 Annex B Table B.1 by this site applying the Chalcedony (Agate/Jasper) row: heat treatment is listed as an enhancement, filling is handled by grade, and dyeing is listed as an enhancement. The full row, including the effect column, is in the chalcedony entry; the notes to Table B.1 and the definitions of the filling grades are on this site's treatments page.
GB/T 16552-2017, Annex B, Table B.1
Under the “Chalcedony (Agate/Jasper)” row of Table B.1: Heating Optimization; Filling Graded — see §5.4.1, Table 1; Dyeing Optimization. The full row, with the effect column, is on the Chalcedony 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
Among the registered material facts for Nanhong Agate, whole-class features such as chemical composition are written in the cited clause for quartzose jade as a whole class and are not listed again for Nanhong Agate; see the Quartzose Jade entry. The Mohs hardness of 6–7, density of 2.53–2.72 g/cm³ and refractive index of 1.53–1.55 likewise take the values for quartzose jade as a whole class and are not measurements of Nanhong Agate alone. GB/T 34098—2017 also notes that Mohs hardness can sometimes fall below 6–7, to as low as 5.5, and density can sometimes fall outside 2.53–2.72 g/cm³, as low as 2.48 g/cm³ or as high as 2.95 g/cm³. This site notes that hardness alone does not amount to any everyday wearing advice, and that the registered density is the main range and cannot be used as a threshold for establishing the material's identity.
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 Nanhong Agate 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 Nanhong Agate (how to read class-level values).
Durability
Stone sold as Nanhong Agate — 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 2026-09-28
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (locator checked 2026-09-28)
- Fact checked on
- 2026-09-28
Physical properties
Stone sold as Nanhong Agate — 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 2026-09-28
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (locator checked 2026-09-28)
- Fact checked on
- 2026-09-28
Optical
Stone sold as Nanhong Agate — 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 2026-09-28
- Source
- GB/T 34098—2017 Quartzose jade — Classification and nomenclature (GB/T): §3.1 (locator checked 2026-09-28)
- Fact checked on
- 2026-09-28
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.
- SAMR / SAC (China). GB/T 16552—2017 Gems — Nomenclature.
- AQSIQ / SAC (China). GB/T 34098—2017 Quartzose jade — Classification and nomenclature.
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.
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Bead-form and unidentified trade terms | Live |
| Treatments recorded for this material | Heated / Heat-treated (via parent 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 Nanhong Agate 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.