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Artificial products / Manufactured products · Artificial product type · Artificial material with no natural counterpart
Artificial Yttrium Aluminium Garnet (YAG)
Also known asYAG
A man-made Y3Al5O12 crystal with no natural gem counterpart; GB/T 16552-2017 Annex A Table A.5 lists it as "man-made yttrium aluminium garnet". 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 Artificial Yttrium Aluminium Garnet (YAG) forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- Caring for and wearing Artificial Yttrium Aluminium Garnet (YAG)Cleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Artificial Yttrium Aluminium Garnet (YAG)Each value with its source and check date
- Artificial Yttrium Aluminium Garnet (YAG) in English, Chinese and Japanese; national standard namesNames in four languages, the GB/T standard name and the suggested listing name, names in national standards; and: Which of GIA, FTC, CIBJO and Gem-A have a name for it on record, and do those agree?
- Listing and disclosing Artificial Yttrium Aluminium Garnet (YAG)The listing name to use; what must be disclosed before sale
- Standard clauses that define Artificial Yttrium Aluminium Garnet (YAG)Which 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
Synthetic yttrium aluminium garnet (YAG, Y3Al5O12) is a man-made crystallised material with no known natural counterpart gem. From the 1960s it joined classic diamond simulants alongside GGG, available as colorless to colored artificial crystals; the colorless crystal is used as uncut material to fashion diamond imitations. CIBJO expressly places yttrium aluminium garnet (YAG) among man-made crystals for which nature offers no equivalent, so it is not a mined gemstone and is not formed in nature.
Scope: Applies to explaining YAG as a man-made crystalline product with no natural counterpart, its positioning as a simulant and its naming requirements; does not apply to descriptions of natural genesis.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Where it forms
Manufacturing environment: artificial crystal growth (e.g. melt growth of single crystals) in a laboratory/factory setting; no natural occurrence environment applies to this record.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Not applicable to a natural occurrence environment: YAG has no known natural counterpart, and no gem-quality natural occurrence exists.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
How it forms, step by step
Prepare the yttrium- and aluminium-oxide feedstock in the Y3Al5O12 stoichiometric ratio.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Grow a single crystal of yttrium aluminium garnet at high temperature by an artificial crystal-growth method.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
(Optional) adjust color by doping during growth to obtain crystals in a range of colors.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Cut and polish: the colorless crystal is used as uncut material to fashion diamond simulants.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Link to appearance
YAG's appearance as a diamond imitation comes from its colorless transparent crystal appearance and optical behavior; the colorless crystal can be faceted into diamond-like finished gems.
Sources GIA Introduction to Imitation Gems
Timescale
The source states YAG joined classic diamond simulants in the 1960s (the material's introduction era, not a geological timescale).
Sources GIA Introduction to Imitation Gems
Other research findings
CIBJO expressly places yttrium aluminium garnet (YAG) among man-made crystals for which nature offers no equivalent — the class of artificial stones.
Evidence grade AScope: Applies to YAG's classification as an artificial stone with no natural counterpart; not to a specific specimen.
Sources CIBJO Gemstone Book 2022
CIBJO requires the name of a man-made crystal with no natural equivalent to be accompanied by 'artificial product' or 'artificial stone', given the same emphasis and prominence as the name.
Evidence grade AScope: Applies to the naming and disclosure of YAG and similar artificial stones; not a value judgment.
Sources CIBJO Gemstone Book 2022
The name of an artificial stone shall not resemble the name, or sound of the name, of any natural material (neither in full, abbreviated, nor by allusion), nor be an established name for another artificial stone.
Evidence grade AScope: Applies to the naming-similarity restriction for artificial stones including YAG; not to specific contract terms.
Sources CIBJO Gemstone Book 2022
In the 1960s, classic diamond simulants such as glass, natural zircon and colourless synthetic spinel were joined by yttrium aluminium garnet (YAG) and its 'cousin' gadolinium gallium garnet (GGG).
Evidence grade AScope: Applies to the historical development of synthetic diamond simulants; not to geologic origin.
Sources GIA Introduction to Imitation Gems
Synthetic yttrium aluminium garnet can be manufactured in a variety of colors; the colorless crystal is used as uncut material to fashion diamond simulants.
Evidence grade AScope: Applies to YAG's color range and the use of colorless material; not to a specimen's color grade.
Sources GIA Introduction to Imitation Gems
Limits of this research
- Research status: Only partial material-specific findings found; gaps are stated as gaps
- The cited sources do not give the specific crystal-growth method (e.g. Czochralski, flux) or process parameters for YAG.
- The sources record no per-specimen chemical composition or doping formulation for YAG.
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
- Man-made Yttrium Aluminium Garnet (YAG)
GB/T 16552—2017 Table A.5 “Yttrium Aluminium Garnet(YAG)” · CIBJO Gemstone Book 2022 4.3.4.1.1
Construction or treatment status
Artificial material with no natural counterpart
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
"Artificial Yttrium Aluminium Garnet (YAG)" is a market name rather than a mineral species name; before using it, verify: Not a mineral: man-made or non-mineral material.
Evidence
- GB/T · Table A.5, row 人造钇铝榴石 (Yttrium Aluminium Garnet (YAG))
What this means for you
Before buying, check the recommended listing name "Man-made Yttrium Aluminium Garnet (YAG)" 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
- Not a mineral: man-made or non-mineral material.
- Suggested listing name
- Man-made Yttrium Aluminium Garnet (YAG)
Care and wear
Care
Artificial Yttrium Aluminium Garnet — care (cleaning): In the GIA 4Cs blog's YAG entry, both ultrasonic and steam cleaning are marked safe.
GIA 4Cs blog (2016)
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- GIA 4Cs blog, “What Are Simulated Diamonds?” (2016-12-20): Section: main text (locator checked 2026-10-06)
- Fact checked on
- 2026-10-06
Artificial Yttrium Aluminium Garnet — care (wear): the same entry credits YAG with good hardness (Mohs 8.5) and high clarity.
GIA 4Cs blog (2016)
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- GIA 4Cs blog, “What Are Simulated Diamonds?” (2016-12-20): Section: main text (locator checked 2026-10-06)
- Fact checked on
- 2026-10-06
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Common care questions and matching entries
Each question links to the matching entries on this page; whether they answer it fully, go by the entry wording.
This table scrolls sideways on narrow screens.
| Question | Matching entries |
|---|---|
| Can it go in an ultrasonic or steam cleaner? | In the GIA 4Cs blog's YAG entry, both ultrasonic and steam cleaning are marked safe |
| Wearing limits (knocks, settings) | the same entry credits YAG with good hardness (Mohs 8.5) and high clarity |
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Artificial Yttrium Aluminium Garnet (YAG), the name register records "YAG", for which no restriction on use as a name is recorded.
Standard and listing namesThe GB/T 16552—2017 formal name for Artificial Yttrium Aluminium Garnet (YAG) is set out in Table A.5, the trade name/synonym is YAG, and the suggested listing name is Man-made Yttrium Aluminium Garnet (YAG). Names in four languagesThe four-language names cover Simplified Chinese, Traditional Chinese, English (Artificial Yttrium Aluminium Garnet (YAG)) and Japanese. National standard namesGermany (RAL) writes Künstlicher YAG and the European Union writes Artificial YAG. Institution usageOn authority wording, GIA has Yttrium Aluminium Garnet (man-made) on record, and CIBJO has Artificial product: YAG, with a qualification stripped from the title name: no natural counterpart; the FTC text on file has no wording for this name (checked), and the wording of Gem-A and of GSJ (Japan) is not yet verified by this site. Japanese namesBodies without a record or not yet checked show the entry's own English or Japanese name, which does not represent their position.
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 (1) | ||||
| YAGEnglish | short form | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- YAG／イットリウム・アルミニウム・ガーネット (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 人造钇铝榴石 (GB/T 16552—2017 Table A.5)
- Mineralogical name
- Manufactured Y3Al5O12 crystal with no natural gem counterpart
- Trade names and synonyms
- YAG (short form)
Four-language names
- 简体中文
- 人造钇铝榴石
- 繁體中文
- 人造釔鋁榴石
- English
- Artificial Yttrium Aluminium Garnet (YAG)
- 日本語
- YAG／イットリウム・アルミニウム・ガーネット
National and regional formal names
- Germany (RAL)
- Künstlicher YAG
- European Union
- Artificial YAG
Qualifiers stripped from the headline name
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Artificial products / Manufactured products
- Material domain
- Artificial products / Manufactured products
- Browsing family
- Artificial gem products with no natural counterpart
- Identity tier
- Artificial product type
- Mineral chemical class
- Mixed / composition-dependent
- Construction or treatment status
- Artificial material with no natural counterpart
What it is and how it's identified
The registered material facts for Artificial Yttrium Aluminium Garnet (YAG): composition is Y3Al5O12; the structure is crystalline, cubic, with a massive crystal habit; Mohs hardness is 8, there is no cleavage, and density is 4.5–4.6 g/cm³; this site notes that hardness alone is not enough to judge durability. The optic character is isotropic, with no birefringence; refractive index is 1.823–1.843, a range derived from the cited clause's 1.833 with a tolerance of ±0.010. When untreated, there is no pleochroism; magnification shows a clean stone with occasional gas bubbles; lustre is vitreous to subadamantine; body colours include colourless, green, blue, pink, red, orange, yellow and purplish red, and green stones may show a colour-change effect. In fluorescence, colourless stones show none to moderate orange under long-wave UV, yellowish green stones strong yellow, and green stones strong red under long-wave UV, possibly with phosphorescence. The UV-visible spectrum of light pink and light blue samples shows several absorption peaks at 600~700nm, and the infrared spectrum shows the characteristic absorption bands of Yttrium Aluminium Garnet in the mid-infrared region.
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”.
Definition
Artificial Yttrium Aluminium Garnet — composition (chemistry): Y3Al5O12
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Structure
Artificial Yttrium Aluminium Garnet — structure (overall): crystalline
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — structure (crystal system): cubic
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — structure (crystal habit): blocky
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Durability
Artificial Yttrium Aluminium Garnet — Mohs hardness: 8
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
- General note
- hardness only, not durability
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — cleavage: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Physical properties
Artificial Yttrium Aluminium Garnet — density: 4.5–4.6 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Optical
Artificial Yttrium Aluminium Garnet — optic character: isotropic material
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — refractive index: 1.823–1.843
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- Qualification
The clause we cite gives 1.833, with a stated tolerance of ±0.010. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — birefringence: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — pleochroism: none
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — fluorescence (overall): colourless: long wave none to moderate, orange; short wave from none to red-orange; pink-red, blue: none; yellow-green: strong, yellow; may be phosphorescent; green: long wave strong, red; short wave weak, red.
GB/T 16553—2017
UV fluorescenceorangenone–moderate, colourlessfrom none to: red-orangeyellowstrong, yellow-greenredstrong, greenredweakDots are illustrative colours built from the colour names, not measured values
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — spectrum (UV-visible): light pink, light blue: 600~700 nm multiple absorption peaks.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — spectrum (infrared): The mid-IR spectrum shows the band pattern typical of YAG
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — optical effect (colour change): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — magnification: clean, occasional bubbles
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Artificial Yttrium Aluminium Garnet — body colour: colourless, green (may show a colour change), blue, pink-red, red, orange, yellow, purple-red and similar colours.
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 Scapolite, Spinel, Cultured Pearl and other variety clauses also name colourless.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
- CIBJO definitions
- colour change
Quality factors
Artificial Yttrium Aluminium Garnet — quality factor (lustre): vitreous to subadamantine
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.15 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
This material (RI / SG midpoints): 1.833 / 4.55; Closest values: 1Smithsonite 1.735 / 4.38, 2Ceylon Sapphire 1.768 / 4.03, 3Burma Ruby 1.768 / 4, 4Garnet 1.825 / 3.9, 5Uvarovite 1.85 / 3.9
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
Clause-level definitions
In the clause-level definitions, man-made Yttrium Aluminium Garnet (YAG) is recorded under the term Yttrium Aluminium Garnet (YAG), citing GB/T 16552—2017 Annex A. The definition given in GB/T 16552—2017 Annex A is a man-made Y3Al5O12 crystal with no natural gem counterpart. The cross-check result is listed directly by GB/T; CIBJO carries no standalone entry under the same name.
This table scrolls sideways on narrow screens.
| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Yttrium Aluminium Garnet (YAG) | GB/T 16552-2017 Annex A | Manufactured Y3Al5O12 crystal with no natural gem counterpart | Listed directly by GB/T; CIBJO carries no standalone entry under the same name. |
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.
- Federal Trade Commission (United States). In the Loupe: Advertising Diamond, Gemstones and Pearls.
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 | Artificial gem products with no natural counterpart | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Artificial Yttrium Aluminium Garnet (YAG) 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.