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Natural inorganic gem materials · Mineral / gemstone variety · Natural identity; treatment status unknown
Sardonyx
Banded Chalcedony made of alternating layers of Sard and onyx; it is listed in CIBJO Gemmological Laboratories Book 2024 §7.2.1.207, while the name does not appear anywhere in GB/T 16552-2017. 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 Sardonyx 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 SardonyxIdentification points from the research literature; how far lab testing can go and whether a synthetic exists
- Treatments and enhancements of SardonyxThe enhancements and treatments the GB/T and JJA/AGL tables list
- Caring for and wearing SardonyxDurability indicators and wearing advice
- Hardness, density and refractive index of SardonyxEach value with its source and check date
- Sardonyx in English, Chinese and Japanese; national standard namesNames in four languages, the GB/T standard name and the suggested listing name; and: Which of GIA, FTC, CIBJO and Gem-A have a name for it on record, and do those agree?
- Name origin and history of SardonyxWhere the name comes from
- Listing and disclosing SardonyxThe listing name to use; what must be disclosed before sale
- Standard clauses that define SardonyxWhich clause defines it, each cross-checked
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
Sardonyx is a banded chalcedony in which red layers (running in the sard/carnelian direction) alternate with onyx layers. Agate is a cryptocrystalline silica material — broadly defined as banded chalcedony — made up chiefly of fibrous microcrystalline low-α quartz together with other silica polymorphs. Why its banding is rhythmic remains incompletely resolved; the leading explanation holds that volcanic-rock cavities are filled in repeated cycles from rim to centre: silica-bearing fluids seep in along microfissures (infiltration canals), and the form and breadth of each zone are governed by the silica concentration together with the temperature, pressure and timing of each fluid pulse. Elements present in the fluids — Fe, Ti, Mn and others — influence only zone colour. Red or red-brown layers arise from a concentration of iron compounds (hematite, goethite). Agate growth may span millions of years, shaped by geochemical processes of both land and sea.
Scope: Applies to the origin of bands and colour bands in banded chalcedony (agate/sardonyx); the specific definitions of the two layer names sard and onyx are not given in the cited sources, and the GB/T clauses cannot be verified.
Sources G&G Fall 2013
Where it forms
Cavities/geodes in volcanic rock (e.g., basalt), cyclically filled by silica-rich fluids
Sources G&G Fall 2013
A supergene to shallow setting influenced by both terrestrial and marine geochemical processes
Sources G&G Fall 2013
How it forms, step by step
A cavity forms in volcanic rock, and silica-rich fluids penetrate via microfissures (infiltration canals).
Fluids fill the cavity cyclically from rim to centre, precipitating fibrous microcrystalline quartz and building banding.
The shape and width of the zones are set by silica concentration and by temperature, pressure and injection timing.
Enrichment in iron compounds (hematite, goethite) forms red or red-brown layers, and other elements determine the colours of the remaining zones.
Link to appearance
Macroscopically it shows alternating light and dark bands; the red layers come from iron-compound enrichment, and the colour and width/shape of the bands are controlled by fluid conditions.
Sources G&G Fall 2013
Timescale
Agate growth at Sidi Rahal, per the source samples, spanned millions of years and proceeded in stages (GIA, 2013).
Sources G&G Fall 2013
Related base materials
- Chalcedony (microcrystalline quartz): variety-of | Sardonyx is the variety of banded chalcedony (agate) with alternating red/black layers
Supporting findings
The prevailing hypothesis for agate (banded chalcedony) is cyclical filling of volcanic voids from rim to centre, with silica-rich fluids entering via microfissures.
Evidence grade AScope: States the banding hypothesis; the mechanism is not fully settled.
Zone dimensions — both shape and width — are controlled by how much silica is present, together with the temperature, pressure and the timing of each fluid pulse; Fe, Ti and Mn and other elements in the fluid influence only the colour of the zones.
Evidence grade AScope: States controls on band geometry and colour; not specific to one locality.
Agate crystallization can last millions of years, taking place in stages influenced by both terrestrial and marine geochemical processes.
Evidence grade AScope: States the timescale of agate crystallization for the study samples (Sidi Rahal).
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Africa
- Madagascar
Sources GIA Birthstones
Asia
- IndiaNotable for good contrast between layers
Sources GIA Birthstones
Europe
- Germany
Sources GIA Birthstones
- CzechiaPrinted as Czechoslovakia
Sources GIA Birthstones
North America
- United States
Sources GIA Birthstones
South America
- Brazil
Sources GIA Birthstones
- Uruguay
Sources GIA Birthstones
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
The red or red-brown layers are caused by enrichment in iron compounds (hematite, goethite).
Evidence grade AScope: States the cause of the red layers; other colour layers excluded.
Where the name comes from
The name sardonyx is not given an etymology by the cited sources; the etymologies belong to its parent minerals: quartz is of obscure origin in the Middle Ages, first applied to gangue in Saxony, Germany. These etymologies belong to those parent minerals, not to the trade name.
Evidence grade BScope: The etymology explains the origin of a name only; it does not attest composition, locality, naturalness or treatment, and here belongs to the parent mineral rather than to the trade name itself.
Sources Handbook of Mineralogy
How it is identified
Banded chalcedony of this kind (red onyx-type) can be dyed or imitated, and the bands and colour on the surface do not prove naturalness or treatment state. Trade rules govern labelling and disclosure but give no diagnostic method; determining a specimen's true material and whether it was treated calls for laboratory testing. The conclusion should be issued by a qualified gem laboratory.
Evidence grade BScope: A conservative call: the listed source provides naming and disclosure rules only, with no material-specific tests.
Sources CIBJO Gemstone Book 2022
Other research findings
Sardonyx denotes banded chalcedony with alternating red and onyx layers; the cited sources do not define the specific layer terms sard and onyx.
Evidence grade CScope: Defines the material class the name denotes; layer definitions and GB/T classification are not asserted.
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The full texts of GB/T 16552-2017 and GB/T 34098-2017 are not obtainable; no clause text was verified and no classification table was invented.
- The cited sources give no authoritative definition of Sardonyx or of the sard/onyx layer terms; the prevailing banding hypothesis is not fully settled.
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
- Sardonyx
CIBJO Gemmological Laboratories Book 2024 §7.2.1.207 “Sardonyx”
Construction or treatment status
Natural identity; treatment status unknown
Treatments recorded for this material: Heated / Heat-treated, Filled / Fracture-filled (via parent material), Dyed
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
Sardonyx is Banded chalcedony variety with alternating sard and onyx layers; use "Sardonyx" for listings, and disclose any known treatments.
Evidence
- CIBJO · 7.2.1.207
What this means for you
Before buying, check the recommended listing name "Sardonyx" and any disclosed treatments on this page, and ask the seller for a grading report if in doubt.
Known uncertainty
- Last reviewed
- 2026-09-01
Care and wear
No care facts are recorded for this entry itself. Its parent material has care records: see Quartz.
Durability and wearing
Toughness
Brittle, tough when massive
Daily wear
Sardonyx is cryptocrystalline quartz (chalcedony) at about Mohs 7 and fairly durable for daily wear; vulnerable to impact cracking and surface abrasion, and if dyed it should be kept from chemicals and heat.
Care
Clean with warm water, mild soap and a soft brush; quartz generally tolerates ultrasonic/steam cleaning, but fractured or treated pieces should be handled cautiously; avoid thermal shock and heavy impact. If dyed, keep it especially away from chemical agents and heat.
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 general material properties and does not constitute a durability or safety warranty for any specific finished product; the durability of treated (filling/dyeing/coating) or assembled pieces must be assessed separately.
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 | — | — |
| heating / colouring | — | — | — | heating / colouring | — |
“—” means the cited source gives no value for that item, not “none”. Source: GB/T 16552—2017 Table B.1 (row for Chalcedony); JJA/AGL 2025
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
The name register below lists one name for Sardonyx in a non-Latin script: 1 with no restriction recorded on use as a name.
Recommended listing nameThe suggested listing name for Sardonyx is Sardonyx. Institution usageCIBJO Gemmological Laboratories Book 2024 lists Sardonyx; FTC has been checked and its text contains no wording for this name; the wording of GIA and Gem-A is not yet verified by this site, and where a body has no recorded wording, the English name shown comes from the entry itself and does not represent that body's position. Chinese standard nameThe full text of GB/T 16552—2017 does not contain this name, which corresponds to agate under the "Chalcedony (Agate/Jasper)" row of Table A.2. Names in four languagesNames are given in Simplified Chinese, Traditional Chinese, English (Sardonyx) and Japanese; on GSJ (Japan), the entry has its own Japanese name, and the wording used by GSJ (Japan) for it is not yet verified by this site. Candidate search termsThe Japanese JJA/AGL gem names handbook 2025 also registers a Japanese transliteration of "sardonyx", which is a search candidate only. The mineralogical description is banded chalcedony with alternating layers of sard and onyx.
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.
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| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (1) | ||||
| サードオニックスJapanese | transliteration | search candidate only | no restriction recorded | JJA/AGL Gemstone Nomenclature 2025 p.11 |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- サードニックス／紅縞瑪瑙 (not yet checked for this body — the entry's own Japanese name is shown)
- GB/T naming counterpart (this name is not in the standard)
- 玛瑙 (GB/T 16552—2017 Table A.2, row “Chalcedony(Agate/Jasper)”)
- Mineralogical name
- Banded chalcedony variety with alternating sard and onyx layers
Four-language names
- 简体中文
- 红缟玛瑙
- 繁體中文
- 紅縞瑪瑙
- English
- Sardonyx
- 日本語
- サードニックス／紅縞瑪瑙
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
- Mineral / gemstone variety
- Mineral chemical class
- Silicates
- Construction or treatment status
- Natural identity; treatment status unknown
Treatments listed by standards
GB/T Table B.1Sardonyx is listed under the Chalcedony (Agate/Jasper) row of GB/T 16552—2017 Annex B Table B.1: heat treatment, classed as an enhancement; filling, graded separately, with definitions on the treatments page; and dyeing, classed as an enhancement. JJA/AGL designationsThe Japanese JJA/AGL table (2025) records Sardonyx under the species quartz, with reddish-brown and white bands; the original has no no-treatment grade, and the heating and colouring listed correspond to heat treatment and dyeing; how to read the JJA/AGL table is explained on the 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.
JJA/AGL (Japan) table of principal gem names, 2025
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| Gem name | Species | Colour | Listed in the table | Notes |
|---|---|---|---|---|
| Sardonyx | Quartz | reddish-brown and white bands | the source lists no untreated tier; heating / colouring (Heated / Heat-treated, Dyed) |
JJA/AGL definitions and nomenclature (2025 revision), table of principal gem names, p.11
How to read the JJA/AGL table: see the Gem treatments page.
What it is and how it's identified
The composition (phase) of Sardonyx is quartz, from the CIBJO definition; whole-class features such as chemical composition are written for chalcedony, including agate and jasper (the whole class). The body colour of Sardonyx is brownish-red to brown bands (the colour of sard) alternating with parallel white and/or black bands, treatment state untreated; this site notes that in chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions for entries such as jadeite, epidote and rhodochrosite also mention red or reddish colours. Taking values for chalcedony, including agate and jasper (the whole class): structure a cryptocrystalline aggregate; Mohs hardness 5–7; density 2.5–2.77 g/cm³; optic character anisotropic aggregate; refractive index 1.535–1.539, with this site noting that the cited clause has finer sub-ranges and the overall value is taken; birefringence not measurable for an aggregate; quality factor (lustre) vitreous to greasy, treatment state untreated.
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 chalcedony, including agate and jasper (the whole class), so they are not repeated on the Sardonyx page; see the material facts on the Chalcedony entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Sardonyx (how to read class-level values).
Definition
Sardonyx — composition (phase): quartz
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Structure
Sardonyx — structure (overall): a cryptocrystalline aggregate, dense and massive in habit; it may also form spherulitic, radial or finely fibrous aggregates.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Sardonyx — Mohs hardness: 5–7
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
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — cleavage: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Sardonyx — density: 2.5–2.77 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Sardonyx — optic character: anisotropic aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — refractive index: 1.535–1.539
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
- General note
- the clause has finer ranges
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — birefringence: not measurable on an aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — pleochroism: not measurable on an aggregate
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — optical effect (iridescence): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — optical effect (chatoyancy): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Sardonyx — body colour: brownish red to brown bands (sard colours) alternating with white and/or black parallel bands.
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- untreated
- Qualification
In chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of Jadeite, Epidote, Rhodochrosite and other entries also name red or a reddish colour.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- Fact checked on
- 2026-09-26
- CIBJO definitions
- chatoyancy
Quality factors
Sardonyx — quality factor (lustre): vitreous to greasy
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- chalcedony, including agate and jasper (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.5 (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): 1.537 / 2.63; Closest values: 1Amethyst 1.548 / 2.67, 2Charoite 1.554 / 2.66, 3Changhua Stone 1.56 / 2.6, 4Shoushan Stone 1.56 / 2.7, 5Balin Stone 1.56 / 2.55
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
In the CIBJO laboratory protocol, Sardonyx is covered under Chalcedony: for identification see the Chalcedony entry, and the list of required tests is on the laboratory testing page. No synthetic counterpart of Sardonyx is available on the market; this finding comes from the CIBJO Blue Book — Official Gemstone Book (2022).
The CIBJO laboratory protocol covers Sardonyx under “Chalcedony” (§6.1.16): see identification on the Chalcedony entry; the required tests are listed on the CIBJO laboratory protocol table for Chalcedony.
How far testing can go
Sardonyx — synthetic counterpart on the market: No synthetic counterpart of this material is commercially available
CIBJO Gemstone Book 2022
- Treatment state
- any treatment state
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Clause-level definitions
Sardonyx has a direct definition in the CIBJO Gemmological Laboratories Book 2024 under the term Sardonyx; the definition gives the mineral species as quartz and the mineral or gemstone variety as sardonyx, and the CIBJO wording is quoted in full under Clause-level definitions on this page. The cross-check result is that it is defined directly by CIBJO; no identically named English entry was found in this edition of the GB/T annex.
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| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Sardonyx | 7.2.1.207 | Onyx showing brownish red to brown bands (sard colours) alternating with white and/or black parallel bands | Defined directly by CIBJO; no identically named English entry was found in this edition of the GB/T annex. |
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.
- RRUFF Project, in partnership with the IMA – International Mineralogical Association. IMA Mineral List.
- Geological Survey of Japan, AIST (Japan). Museum mineral specimens, browse by classification.
Further reading
Recorded cultural contexts
Japan's JJA 2021 revised roster lists Sardonyx for August. This records trade-association convention only; it does not establish material identity, natural origin, treatment, provenance, or effect.
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| Publisher or holder | Region | From / period | Source and locator |
|---|---|---|---|
| Japan Jewellery Association | Japan | from 20 December 2021 | Tanjoseki (Japanese birthstone roster, Japan Jewellery Association page; revision of 20 December 2021) 2021 revised birthstone roster, August row: Sardonyx |
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 (Sardonyx) 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
- 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 |
| Treatments recorded for this material | Heated / Heat-treated, Filled / Fracture-filled (via parent material), Dyed | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Sardonyx 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; clause-level definitions also carry a cross-check result. The entry exists so that buyers and sellers can check naming, disclosure and material facts item by item.