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Artificial products / Manufactured products · Artificial product type · Synthetic product
Synthetic Sapphire
Synthetically made corundum, the counterpart of natural Sapphire; GB/T 16552-2017 Annex A Table A.4 lists it as "synthetic sapphire", with the colour stated separately. 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 Synthetic Sapphire 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 Synthetic SapphireIdentification points from the research literature
- Hardness, density and refractive index of Synthetic SapphireEach value with its source and check date
- Synthetic Sapphire 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: Do GIA, FTC, CIBJO and Gem-A use the same wording for it?
- Listing and disclosing Synthetic SapphireThe listing name to use; what must be disclosed before sale
- Standard clauses that define Synthetic SapphireWhich 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 sapphire is man-made blue corundum whose natural counterpart is sapphire. Its blue colour is caused by iron and titanium deliberately added (the Fe2+-Ti⁴⁺ pair), the same colouring mechanism as natural sapphire. It is usually manufactured by melt-growth methods—for example the Czochralski pulling technique growing single crystals from a Fe-Ti-doped Al2O3 melt; colourless synthetic sapphire is also widely used as an optical/window material. Under CIBJO rules, synthetic sapphire must be clearly labelled “synthetic sapphire / laboratory-grown sapphire” and must not be called simply sapphire.
Scope: Applies to synthetic corundum that is artificially manufactured, coloured by Fe-Ti and corresponds to natural sapphire; colourless synthetic sapphire used as an optical material is covered only at the level of composition and structure.
Sources CIBJO Gemstone Book 2022 · G&G Spring 2020
Where it forms
An artificial crystal-growth setting: high-temperature melts and laboratory/factory crystal-growth facilities (e.g., Czochralski pullers), not a natural geological environment.
Sources CIBJO Gemstone Book 2022 · G&G Spring 2020
How it forms, step by step
Prepare a Fe-Ti-doped Al2O3 charge: a high-purity alumina base with iron and titanium added as the blue colorants.
Grow corundum single crystal by a melt method: grow blue corundum from the melt at high temperature (near its ~2050°C melting point), e.g., by the Czochralski technique.
Anneal, cut and polish, and clearly label the product as “synthetic sapphire”.
Link to appearance
Synthetic sapphire is blue because the deliberately added Fe2+-Ti⁴⁺ pair absorbs strongly in the yellow and red, the same colouring mechanism as natural sapphire; with composition and structure matching natural sapphire, basic gemological properties are similar, and identification rests mainly on internal growth features.
Sources CIBJO Gemstone Book 2022 · G&G Spring 2020
Timescale
The cited sources mention a melt-growth temperature of about 2050°C for sapphire; no general full production timescale is given.
Sources CIBJO Gemstone Book 2022 · G&G Spring 2020
Related base materials
- Synthetic corundum: Higher-level category: synthetic sapphire is blue (or colourless/other-coloured) synthetic corundum
- Corundum (Al2O3): Synthetic counterpart: its natural counterpart is sapphire
- Alumina (Al2O3) nutrient powder: Raw material/precursor for artificial crystal growth, doped with iron and titanium (Fe, Ti) to obtain a blue colour
Supporting findings
Synthetic sapphire can be grown by the Czochralski method from a high-temperature melt—for example the Fe-Ti-doped synthetic blue sapphire grown for chromophore research.
Evidence grade AScope: The pulling method used in the research is an example; industry also uses other melt methods such as flame fusion.
Causes of colour and optical effects
The blue of synthetic sapphire is caused by the Fe2+-Ti⁴⁺ pair, which absorbs strongly in the yellow and red, the same colouring mechanism as natural sapphire.
Evidence grade AScope: Concerns the Fe2+-Ti⁴⁺ pair mechanism; other colouring routes for blue synthetic corundum are not exhaustively covered.
How it is identified
Synthetic sapphire can look like natural or treated sapphire, and a single observation rarely settles it. A laboratory combines several approaches: microscopy to assess coatings and fillings, Fourier-transform infrared, ultraviolet/visible/near-infrared and laser Raman spectroscopy to confirm the phase and absorption features, and energy-dispersive X-ray fluorescence to identify coating or introduced elements; the conclusion must be issued by an accredited laboratory.
Evidence grade AScope: Synthetic sapphire identification and treatment judgement are done in a laboratory, with the conclusion from an accredited body.
Sources G&G Fall 2019
Synthetic sapphire is man-made blue corundum. Such material is man-made, so natural origin determination does not apply. Origin determination is meaningful only for natural stones: for synthetic material the synthesis or treatment status has to be settled first, and a place name attached to it is at most a brand or a place of manufacture, not a geological source. Any separation of species or naturalness must be issued by a qualified laboratory for a specific specimen, and origin cannot be inferred from appearance or name.
Evidence grade AScope: Origin cannot be inferred from appearance or name; an origin conclusion must be issued by a qualified laboratory for a specific specimen, and this entry provides no self-test criteria or thresholds.
Sources G&G Winter 2019 · G&G Summer 1998 · G&G Spring 2015 +1
- Geographic Origin Determination of Ruby (Gems & Gemology, Winter 2019, Vol. 55, No. 4)
- Separating Natural and Synthetic Rubies on the Basis of Trace-Element Chemistry (Gems & Gemology, Summer 1998, Vol. 34, No. 2)
- Mozambique Ruby Discovery: A 21st Century Rush (Gems & Gemology, Spring 2015, Vol. 51, No. 1)
- Sapphire Beneath the Rich Black Soil of Muling, Northeastern China (Gems & Gemology, Fall 2022, Vol. 58, No. 3)
Other research findings
Synthetic sapphire is man-made synthetic corundum corresponding to natural sapphire and must be labelled as “synthetic sapphire”.
Evidence grade AScope: Uses CIBJO’s synthetic-stone definition and naming rule; no commercial brand involved.
Sources CIBJO Gemstone Book 2022
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- Synthetic/man-made information comes from the CIBJO definition and GIA laboratory research; details of historical patented processes come from a literature review and do not represent the specific process of all synthetic corundum on the market.
- The growth methods cited (Verneuil, Czochralski) are examples; other melt-growth or flux methods can also produce the same 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
- Synthetic Sapphire
GB/T 16552—2017 Table A.4 “Synthetic Sapphire” · CIBJO Gemstone Book 2022 4.3.3.1
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
"Synthetic Sapphire" 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.4, row 合成蓝宝石 (Synthetic Sapphire)
What this means for you
Before buying, check the recommended listing name "Synthetic Sapphire" 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
- Synthetic Sapphire
Care and wear
No care facts are recorded for this entry itself. Its parent material has care records: see Sapphire.
VerifyNames, standards, technical facts, clauses and sources
Names
Standard and listing namesThe Chinese formal name for Synthetic Sapphire is set out in GB/T 16552—2017 Table A.4, and the suggested listing name is Synthetic Sapphire. Institution usageOn authority wording, GIA has Laboratory-grown Sapphire on record, FTC has Laboratory-created Sapphire, CIBJO has Synthetic Sapphire and Gem-A has Synthetic Sapphire; the GSJ (Japan) wording for the entry's own Japanese name is not yet verified by this site. Names in four languagesThe four-language names cover Simplified Chinese, Traditional Chinese, English (Synthetic Sapphire) and Japanese. Trade and mineralogical namesThe mineralogical name is synthetic corundum corresponding to sapphire. National standard namesNational and regional formal names: Germany (RAL) Synthetischer Saphir, European Union Synthetic Sapphire, France (DGCCRF) Saphir synthétique, and Thailand (GIT) Synthetic Sapphire, noting that it is widely produced in Chanthaburi.
- GSJ (Japan) formal name
- 合成サファイア (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 合成蓝宝石 (GB/T 16552—2017 Table A.4)
- Mineralogical name
- Synthetic corundum corresponding to sapphire
Four-language names
- 简体中文
- 合成蓝宝石
- 繁體中文
- 合成藍寶石
- English
- Synthetic Sapphire
- 日本語
- 合成サファイア
National and regional formal names
- Germany (RAL)
- Synthetischer Saphir
- European Union
- Synthetic Sapphire
- Thailand (GIT)
- Synthetic Sapphire; widely produced in Chanthaburi
- France (DGCCRF)
- Saphir synthétique
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Artificial products / Manufactured products
- Material domain
- Artificial products / Manufactured products
- Browsing family
- Synthetic gem products
- Identity tier
- Artificial product type
- Mineral chemical class
- Mixed / composition-dependent
- Construction or treatment status
- Synthetic product
What it is and how it's identified
The composition (chemistry) of Synthetic Sapphire is Al2O3, which may contain elements such as Fe, Ti, Cr and V; the structure is crystalline, the crystal system trigonal, and the crystal habit is pear-shaped boules from the flame-fusion process, with flux-grown and hydrothermal crystals both tabular. Mohs hardness is 9; a further note states that hardness alone is not enough to judge durability. There is no cleavage. Density is 3.95–4.1 g/cm³; the qualification notes that the cited clause gives 4.00 with a stated tolerance (+0.10, −0.05), from which the limits are derived. The optic character is anisotropic, uniaxial, negative; refractive index is 1.757–1.779; the qualification notes that the cited clause gives 1.762–1.770 with a stated tolerance (+0.009, −0.005), from which the limits are derived; birefringence is 0.008–0.01. For untreated Synthetic Sapphire, the quality factor (lustre) is vitreous. As for optical effects, chatoyancy is visible but rare, asterism is visible, and colour change is visible.
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
Synthetic Sapphire — composition (chemistry): Al2O3;elements such as Fe,Ti,Cr and V may be contained.
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Structure
Synthetic Sapphire — 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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — structure (crystal system): trigonal
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — structure (crystal habit): pear-shaped boules (flame fusion); plates (flux melt and hydrothermal growth).
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Durability
Synthetic Sapphire — Mohs hardness: 9
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — 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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Physical properties
Synthetic Sapphire — density: 3.95–4.1 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- Qualification
The clause we cite gives 4.00, with a stated tolerance of +0.10 / -0.05. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Optical
Synthetic Sapphire — optic character: uniaxial, optically negative (anisotropic)
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — refractive index: 1.757–1.779
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- Qualification
The clause we cite gives 1.762–1.770, with a stated tolerance of +0.009 / -0.005. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — birefringence: 0.008–0.01
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — pleochroism: blue: blue and green-blue; green: green and yellow-green; colour-change material: purple and purple-blue; pink: pink and pink-red; orange-yellow: yellow and orange-yellow.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-22
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.3 (locator checked 2026-09-22)
- Fact checked on
- 2026-09-22
Synthetic Sapphire — fluorescence (overall): blue: long wave none; short wave weak to moderate, blue-white, yellow-green; green: long wave weak, orange; short wave brown-red; pink: long wave moderate to strong, red; short wave red-pink; yellow: short wave very weak, red; colourless: none to weak, blue-white; colour-change: moderate, orange-red.
GB/T 16553—2017
UV fluorescenceblue-whiteyellow-greenweak–moderateorangeweak, greenbrown-redredmoderate–strong, pinkred-pinkredvery weak, yellowblue-whitenone–weak, colourlessorange-redmoderate, colour-changeDots 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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — spectrum (UV-visible): blue: none; flux-grown synthetic sapphire: may have 450 nm weak absorption peak; green: 530 nm absorption peak; 687 nm absorption peak; orange, violet, pink: 690 nm absorption peak; 650 nm absorption peak; 670 nm absorption peak; 510~580 nm broad absorption band; colour-change: 474 nm absorption peak.
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — spectrum (infrared): Al-O vibration in corundum gives diagnostic mid-IR bands. Hydrothermally grown synthetic sapphire departs from natural sapphire in its functional-group-region bands (OH, mineralizers and so on).
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-22
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.3 (locator checked 2026-09-22)
- Fact checked on
- 2026-09-22
Synthetic Sapphire — optical effect (chatoyancy): seen; uncommon
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — optical effect (asterism): 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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — 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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — magnification: flame fusion method: curved growth striations, bubble, unmelted residues; flux method: fingerprint-like inclusions, flux residues in bundles, gauzy veils, spheres or minute droplets, metal plates of hexagonal or triangular outline; hydrothermal method: branching (dendritic) growth striations, color band, gold-coloured metal flakes, colourless, transparent inclusions forming a gauze-like mesh, or nail-shaped ones.
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): §5.4.3 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Synthetic Sapphire — body colour: blue, green, purple-blue (color change), pink, yellow, orange and colorless.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- Qualification
The colours GB/T 16553—2017 lists for Sapphire overlap with this entry: blue, green, yellow, orange, pink and colourless.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.3 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
- CIBJO definitions
- chatoyancy, asterism, colour change
Quality factors
Synthetic Sapphire — quality factor (lustre): vitreous
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): §5.4.3 (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): 1.768 / 4.03; Closest values: 1Rhodolite 1.755 / 3.9, 2Almandine 1.79 / 3.9, 3Grossular 1.745 / 3.9, 4Tsavorite 1.74 / 3.9, 5Spessartine 1.802 / 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, Synthetic Sapphire is recorded under the term Synthetic Sapphire, based on GB/T 16552—2017 Annex A, with the recorded definition synthetic corundum corresponding to sapphire. 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 |
|---|---|---|---|
| Synthetic Sapphire | GB/T 16552-2017 Annex A | Synthetic corundum corresponding to sapphire | 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.
Related-entry tree for Corundum on this site: 18 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Synthetic Sapphire) is marked.
- Corundum
Sub-entries (13)
- Colour-change Sapphire
- Green Sapphire
- Orange Sapphire
- Padparadscha Sapphire
- Pink Sapphire
- Purple Sapphire
- Ruby
Sub-entries (2)
- Lead-Glass-Filled Ruby
- Synthetic Ruby (Synthetic product)
- Sapphire
Sub-entries (2)
- Beryllium-Diffused Sapphire
- Synthetic Sapphire (Synthetic product)
- Star Ruby
- Star Sapphire
- Synthetic Corundum (Synthetic product)
- White Sapphire
- Yellow Sapphire
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Synthetic gem products | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Synthetic Sapphire 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.