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UnderstandWhat it is, what people ask, how far this page goes
Artificial products / Manufactured products · Artificial product type · Man-made glass
Man-made Glass
Artificial glass, as distinguished from natural glass. Under GB/T 16552-2017 clause 5.1.3.2 a), "glass" and "plastic" do not take the prefix "man-made", so this name does not follow the naming rules. 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 Man-made Glass forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- Caring for and wearing Man-made GlassCleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Man-made GlassEach value with its source and check date
- Man-made Glass 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 Man-made GlassThe listing name to use; what must be disclosed before sale
- Standard clauses that define Man-made GlassWhich 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
Man-made glass is a product of artificial melting. CIBJO describes glass in general as a non-crystalline material, occurring naturally or made artificially, that has hardened out of a melt and normally consists of a mixture of oxides (for example silicon, sodium, calcium, aluminium and lead). The 'man-made' subset is the artificially produced form, grouped by CIBJO among artificial uncrystallised products. It is widely used as a gem imitation (for instance of amethyst, aquamarine or peridot) and can be fashioned to resemble phenomenal gems such as tiger's eye and opal. It is a category distinct from natural glass (compare the Natural Glass entry, where glass arises through rapid natural cooling).
Scope: Applies to explaining the man-made, melt-produced nature of man-made glass, its use as an imitation, and how it is distinguished from natural glass (see the Natural Glass entry); does not describe the origin of natural glass.
Sources CIBJO Gemstone Book 2022
Where it forms
Natural occurrence environment does not apply: man-made glass is melted at high temperature in a furnace/workshop and solidified on cooling, not formed in nature.
Sources CIBJO Gemstone Book 2022
Production conditions: a high-temperature melt, usually a mixture of oxides, rapidly cooled so that no ordered crystal structure forms (amorphous).
Sources CIBJO Gemstone Book 2022
How it forms, step by step
Prepare the oxide feedstock (e.g. oxides of silicon, sodium, calcium, aluminium, lead) and colorants for the desired color and properties.
Sources CIBJO Gemstone Book 2022
Melt the mixture at high temperature into a homogeneous melt.
Sources CIBJO Gemstone Book 2022
Cool and solidify; because it is not allowed to crystallise, an amorphous glass results.
Sources CIBJO Gemstone Book 2022
Shape, cut and polish into finished pieces as needed, and name/disclose it truthfully as glass or an imitation.
Sources CIBJO Gemstone Book 2022
Link to appearance
Man-made glass can be made in virtually any color, so it can substitute for many gems; it can also be made to look like phenomenal gems such as tiger's eye and opal, and fused glass layers can imitate agate, malachite or tortoise shell. It is, however, usually less brilliant than the gems it imitates.
Sources CIBJO Gemstone Book 2022 · GIA Introduction to Imitation Gems
Timescale
The cited authorities give no melting duration or specific date for man-made glass.
Sources CIBJO Gemstone Book 2022
Supporting findings
Man-made glass is produced by artificially melting oxide feedstock at high temperature and solidifying it on cooling (amorphous, without an ordered crystal lattice).
Evidence grade AScope: States the artificial melting route and man-made nature; gives no specific recipe or temperature.
Sources CIBJO Gemstone Book 2022
Other research findings
CIBJO characterises glass as a non-crystalline material — whether it occurs in nature or is made by humans — that has solidified out of a melt and normally consists of a mixture of oxides.
Evidence grade AScope: A terminology definition covering both natural and artificial glass; this record focuses on the artificial branch.
Sources CIBJO Gemstone Book 2022
CIBJO classifies man made glass among artificial uncrystallised products and separately defines 'lead glass' as artificially produced glass with a high lead-oxide content.
Evidence grade AScope: Classification and a sub-term; not about use or value.
Sources CIBJO Gemstone Book 2022
Man-made glass is a material category distinct from natural glass: CIBJO's definition covers both natural and artificial glass, the former formed naturally and the latter produced by melting (natural glass is covered by the Natural Glass entry).
Evidence grade AScope: Distinguishes the man-made and natural glass categories; it does not describe natural-glass formation (see the Natural Glass entry).
Sources CIBJO Gemstone Book 2022
Man-made glass is a common gem imitation: GIA calls it an age-old gem imitation used for stones such as amethyst, aquamarine and peridot, and it can be made to look like tiger's eye and opal.
Evidence grade AScope: Describes its imitative use; not all glass items are imitations.
Sources GIA Introduction to Imitation Gems
This entry and the Glass entry describe the same kind of material, man-made glass, and can be read together; both differ from natural glass (see the Natural Glass entry).
Evidence grade AScope: Entry-relationship/deduplication note; no process detail.
Sources CIBJO Gemstone Book 2022
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- This entry and the Glass entry describe the same material, man-made glass, and can be read together; both are distinct from natural glass (see the Natural Glass entry).
- The cited authorities give no specific recipe, melting temperature or duration for man-made glass.
- 'Glass' is a broad term; the composition and process of any specific glass item must be tested separately.
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 glass
GB/T 16552—2017 5.1.3.2 a) · CIBJO Gemstone Book 2022 4.3.5.1
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
"Man-made Glass" 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 · 5.1.3.2 a)
What this means for you
Before buying, check the recommended listing name "Man-made glass" 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 glass
Care and wear
Care
Man-made Glass — care (cleaning): Glass beads stitched onto garments should never be washed with water, since the thread and the textile or leather can be harmed.
NPS Museum Handbook, Appendix P
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- National Park Service, Museum Handbook Part I, Appendix P: Curatorial Care of Ceramic, Glass, and Stone Objects (2000): p.P:19, body text (locator checked 2026-10-06)
- Fact checked on
- 2026-10-06
Man-made Glass — care (light): Prolonged sunlight can make certain glass turn purple or brown, an effect called solarization.
NPS Museum Handbook, Appendix P
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- National Park Service, Museum Handbook Part I, Appendix P: Curatorial Care of Ceramic, Glass, and Stone Objects (2000): p.P:11, body text (locator checked 2026-10-06)
- Fact checked on
- 2026-10-06
Man-made Glass — care (storage): for unstable 'weeping' glass, keeping relative humidity low slows further decay.
NPS Museum Handbook, Appendix P
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- National Park Service, Museum Handbook Part I, Appendix P: Curatorial Care of Ceramic, Glass, and Stone Objects (2000): p.P:16, body text (locator checked 2026-10-06)
- Fact checked on
- 2026-10-06
Man-made Glass — care (wear): Glass is mostly damaged by physical force; it breaks and chips readily.
NPS Museum Handbook, Appendix P
- Treatment state
- any treatment state
Source & check 2026-10-06
- Source
- National Park Service, Museum Handbook Part I, Appendix P: Curatorial Care of Ceramic, Glass, and Stone Objects (2000): p.P:11, body 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? | Glass beads stitched onto garments should never be washed with water, since the thread and the textile or leather can be harmed |
| Light and display | Prolonged sunlight can make certain glass turn purple or brown, an effect called solarization |
| Wearing limits (knocks, settings) | Glass is mostly damaged by physical force; it breaks and chips readily |
VerifyNames, standards, technical facts, clauses and sources
Names
Standard and listing namesFor the GB/T name of Man-made Glass, the standard does not list this name itself; the basic name for man-made gems in GB/T 16552—2017 Table A.5 is Glass, and the suggested listing name is Man-made glass. Trade and mineralogical namesMan-made Glass is a trade name, not a mineral species name. Names in four languagesThe Simplified and Traditional Chinese names are written the same, the English name is Man-made Glass, and there is a Japanese name; the mineralogical name means man-made glass, as distinct from natural glass. National standard namesThe formal name in Germany (RAL) is Künstliches Glas, and in the European Union Artificial Glass. Institution usageFor authority wording, CIBJO records Artificial product: Glass; the FTC text on file has no wording for this name (checked); GIA and Gem-A are unchecked. Bodies without a recorded wording show the entry's own English name, Man-made Glass, which does not represent their position. Japanese namesThe Japanese name shown in the GSJ (Japan) formal-name field is the entry's own, and GSJ's wording for man-made glass is not yet verified by this site.
- GSJ (Japan) formal name
- 人造ガラス (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)
- 玻璃 (GB/T 16552—2017 §5.1.3.2 a))
- Mineralogical name
- Man-made glass distinguished from natural glass
Four-language names
- 简体中文
- 人造玻璃
- 繁體中文
- 人造玻璃
- English
- Man-made Glass
- 日本語
- 人造ガラス
National and regional formal names
- Germany (RAL)
- Künstliches Glas
- European Union
- Artificial Glass
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Artificial products / Manufactured products
- Material domain
- Artificial products / Manufactured products
- Browsing family
- Man-made glass products
- Identity tier
- Artificial product type
- Mineral chemical class
- Not applicable
- Construction or treatment status
- Man-made glass
What it is and how it's identified
The material and identification facts for Man-made Glass are registered by GB/T 16553—2017 under man-made glass (the whole category); they are category values, not separately measured data. For man-made glass as a whole category, the overall structure is amorphous, Mohs hardness is 5–6, there is no cleavage and density is 2.3–4.5 g/cm³, the hardness and density being usual, typical values rather than absolute limits; optically it is isotropic, commonly with anomalous optical behaviour, the refractive index is 1.47–1.7, this site noting that the clause also has finer sub-ranges and the overall value is registered, and there is no birefringence. Among the optical effects of man-made glass as a whole category, play-of-colour, iridescence, cat's-eye effect, star effect, aventurescence, colour-change effect and sheen may all be seen; pleochroism and lustre are registered for untreated man-made glass, with no pleochroism and a vitreous lustre. Chemical composition, fluorescence, UV-Vis spectrum, infrared spectrum and magnification are written in the cited clauses for man-made glass (the whole category).
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 manufactured glass (whole class), so they are not repeated on the Man-made Glass page; see the material facts on the Glass entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Man-made Glass (how to read class-level values).
Structure
Man-made Glass — structure (overall): amorphous (not crystalline)
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Man-made Glass — Mohs hardness: 5–6
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
- manufactured glass (whole class)
- Qualification
The clause we cite gives this as a typical value. It is a common value, not an absolute limit.
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — cleavage: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Man-made Glass — density: 2.3–4.5 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
- Qualification
The clause we cite gives this as a typical value. It is a common value, not an absolute limit.
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Man-made Glass — optic character: isotropic, commonly with anomalous optical behaviour
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — refractive index: 1.47–1.7
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
- General note
- the clause has finer ranges
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — birefringence: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — pleochroism: none
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (play of colour): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (iridescence): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (chatoyancy): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (asterism): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (aventurescence): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (colour change): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Man-made Glass — optical effect (labradorescence): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
- CIBJO definitions
- play of colour, chatoyancy, asterism, aventurescence, colour change, labradorescence
Quality factors
Man-made Glass — quality factor (lustre): vitreous
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- manufactured glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.4.20 (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): 1.585 / 3.4; Closest values: 1Hemimorphite 1.625 / 3.45, 2Imperial Topaz 1.623 / 3.53, 3Lazulite 1.627 / 3.12, 4Apatite 1.639 / 3.18, 5Synthetic Jadeite 1.66 / 3.34
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
The clause-level definition of Man-made Glass is registered as Man-made Glass, based on GB/T 16552—2017 Annex A, defined as man-made glass as distinguished from natural glass. The cross-check result is that it 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 |
|---|---|---|---|
| Man-made Glass | GB/T 16552-2017 Annex A | Man-made glass distinguished from natural glass | 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 | Man-made glass products | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Man-made Glass 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.