On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Mineral species · Natural identity; treatment status unknown
Quartz
A mineral species with the formula SiO2, the parent species of varieties such as rock crystal, chalcedony, agate and jasper; under GB/T 16552-2017 clause 5.1.1 b) it can be used directly as a gem name. 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.
Questions people ask about Quartz
Every sentence below is followed by the registered fact it rests on; answers add no new facts and promise no outcome.
Q1Why do quartz beads come in so many colours?
Pure quartz is colourless and transparent; chemical or particulate inclusions can make it rose-pink, yellow-brown, green, blue, violet, or brown to black.Handbook of Mineralogy · G&G Spring 2017Low-grade radiation over a geological time span can give quartz its amethystine colour.Handbook of Mineralogy · G&G Spring 1982Later high-temperature events, such as extruding volcanic bodies, can change amethyst to citrine or green quartz.Handbook of Mineralogy · G&G Spring 1982
Q2Is quartz jewellery ever dyed, irradiated or otherwise treated?
Yes: irradiated quartz sold under a colour name may fade or revert to its original colour in strong light, so it should not be worn or left in strong light for long periods.CIBJO Gemstone Book 2022For dyed iris quartz, the dye treatment is not permanent, so it should be kept away from all solvents, including dish-washing liquids, chemicals and heat.CIBJO Gemstone Book 2022Treated iris quartz should not be cleaned ultrasonically.CIBJO Gemstone Book 2022Whether one particular bead is natural, treated or synthetic — only a laboratory report can settle that.What this page can answer
Q3How hard and durable is quartz in jewellery?
Quartz is recorded at 7 on the Mohs scale.Handbook of MineralogyIt is brittle, though tough when massive.Handbook of MineralogyFor transparent quartz other than amethyst and citrine, prong and bezel settings are rated relatively safe, while flush, channel and pavé settings should be avoided, since the stone may be included or fractured.Gems & Gemology 1987 (Martin)
Q4How should quartz jewellery be cleaned?
For transparent quartz other than amethyst and citrine, ultrasonic and steam cleaning call for caution, and thermal shock should be avoided.Gems & Gemology 1987 (Martin)The same record warns that thermal shock may fracture it and that heat turns smoky quartz colourless.Gems & Gemology 1987 (Martin)
Q5Does quartz have healing powers?
There is no scientific evidence that quartz has healing powers: the UK advertising regulators ASA and CAP state that they have not seen evidence that crystal therapy can treat medical conditions.ASA/CAP guidance (UK)
Sources cited in these answers ASA/CAP guidance (UK)
What this page can answer
This page covers
- How Quartz 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 QuartzIdentification points from the research literature; how far lab testing can go
- Treatments and enhancements of QuartzThe enhancements and treatments the GB/T and JJA/AGL tables list
- Caring for and wearing QuartzCleaning, heat, chemicals and light, as the cited sources give them; durability indicators and wearing advice
- Hardness of QuartzEach value with its source and check date
- Quartz 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 QuartzWhere the name comes from
- Listing and disclosing QuartzThe listing name to use; what must be disclosed before sale
- Standard clauses that define QuartzWhich 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
Quartz (SiO2) is one of the most common rock-forming mineral species, a hexagonal silicon oxide that is nearly pure SiO2 with traces of other elements. It occurs widely in hydrothermal veins, in granites and granite pegmatites, in sandstones and quartzites, in carbonate rocks and in hydrothermal metal deposits, and is a residual mineral in soils and sediments. Quartz is stable below 573 C and has several polymorphs (cristobalite, tridymite, coesite, stishovite). Certain coloured quartz such as green quartz can form naturally when amethyst is altered by radiation and later thermal events.
Scope: Applies to an overview of the formation, occurrence, composition and polytypes of quartz as a mineral species; the origins of colour varieties (amethyst, citrine, green quartz, etc.) are dealt with separately in the corresponding entries.
Sources Handbook of Mineralogy · G&G Spring 1982
Where it forms
Veins of hydrothermal origin (epithermal through alpine), together with granites and granite pegmatites.
Sources Handbook of Mineralogy · G&G Spring 1982
Sedimentary rocks such as sandstones and quartzites, carbonate rocks and hydrothermal metal deposits; also a residual mineral in soils and sediments.
Sources Handbook of Mineralogy · G&G Spring 1982
How it forms, step by step
Silica is slowly deposited from migrating silica-bearing solutions.
Sources Handbook of Mineralogy · G&G Spring 1982
Quartz crystallizes as crystals in hydrothermal veins, vugs or pegmatite cavities.
Sources Handbook of Mineralogy · G&G Spring 1982
Low-grade radiation over a geological time span can give quartz its amethystine colour.
Sources Handbook of Mineralogy · G&G Spring 1982
Subsequent high-temperature events (e.g. extruding volcanic bodies) can change amethyst to citrine or green quartz.
Sources Handbook of Mineralogy · G&G Spring 1982
Link to appearance
Pure quartz is colourless and transparent; chemical or particulate inclusions can make it rose-pink, yellow-brown, green, blue, violet, brown to black. Green quartz colour relates to natural irradiation and later thermal events.
Sources Handbook of Mineralogy · G&G Spring 2017
Timescale
Quartz is stable below 573 C; colour changes involve low-grade radiation over a geological time span and subsequent thermal events.
Sources Handbook of Mineralogy · G&G Spring 1982
Supporting findings
Quartz occurs in hydrothermal veins (epithermal to alpine), is characteristic of granites and granite pegmatites, and is found in sandstones and quartzites, in carbonate rocks and in hydrothermal metal deposits.
Evidence grade BScope: Describes the natural occurrence of quartz; not laboratory growth conditions.
Sources Handbook of Mineralogy
Quartz can form naturally by slow deposition of silica from migrating solutions and crystallize in rock cavities; green quartz can form naturally when amethyst is altered by low-grade radiation and subsequent high-temperature thermal events into citrine or green quartz.
Evidence grade AScope: Applies to naturally colour-changed quartz such as green quartz; no artificial treatment involved.
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Africa
- Tamboholehehibe and elsewhere, Madagascar
Sources Handbook of Mineralogy
Asia
- Sakangyi, Katha, Sagaing, Myanmar
Sources Handbook of Mineralogy
- Yamanashi Prefecture, Japan
Sources Handbook of Mineralogy
Europe
- Swiss Alps, Switzerland
Sources Handbook of Mineralogy
- Austrian Alps, Austria
Sources Handbook of Mineralogy
- Carrara, Tuscany, Italy
Sources Handbook of Mineralogy
- Bourg d'Oisans, Isère, France
Sources Handbook of Mineralogy
- Murzinka and Dodo mine, Ural Mountains, Russia
Sources Handbook of Mineralogy
North America
- Thunder Bay, Ontario, Canada
Sources Handbook of Mineralogy
- Mount Ida to Hot Springs, Ouachita Mountains, Arkansas, United States
Sources Handbook of Mineralogy
- Middleville, Herkimer County, New York, United States
Sources Handbook of Mineralogy
- Alexander and Lincoln counties, North Carolina, United States
Sources Handbook of Mineralogy
- Pala and Mesa Grande districts, San Diego County, California, United States
Sources Handbook of Mineralogy
- El Capitan Mountains, Lincoln County, New Mexico, United States
Sources Handbook of Mineralogy
- Crystal Park and Little Pipestone Creek, Montana, United States
Sources Handbook of Mineralogy
- Pikes Peak area, Colorado, United States
Sources Handbook of Mineralogy
- Veracruz and Guerrero, Mexico
Sources Handbook of Mineralogy
South America
- Rio Grande do Sul, Brazil
Sources Handbook of Mineralogy
- Minas Gerais, Brazil
Sources Handbook of Mineralogy
- Goiás, BrazilGoiás is broken in the HoM text layer
Sources Handbook of Mineralogy
- Bahia, Brazil
Sources Handbook of Mineralogy
- Artigas area, Uruguay
Sources Handbook of Mineralogy
Seas and coasts
- WorldwideHoM: extraordinarily common
Sources Handbook of Mineralogy
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
In some natural quartz (e.g. iris quartz from India's Deccan Traps) the iridescence is not a thin-film effect but is caused by surface grooving together with an underlying lamellar structure forming a diffraction grating.
Evidence grade AScope: Applies to natural iris quartz; not to artificial metal-coated 'aurora quartz'.
Where the name comes from
The name quartz was first applied in the Middle Ages to gangue in Saxony, Germany, and its etymology is obscure.
Evidence grade BScope: The etymology explains the origin of a name only; it does not attest composition, locality, naturalness or treatment.
Sources Handbook of Mineralogy
How it is identified
A quartz's colour and appearance do not prove whether it is natural or synthetic. Laboratory identification normally combines microscopic twinning and colour zoning, chemical analysis such as EDXRF, infrared spectroscopy, and where needed a polariscope (conoscope) or refractometer to read how a colour boundary relates to the optic axis. Interpretation depends on a specialist's grasp of the material's optics and morphology, so the conclusion should be issued by a qualified gem laboratory.
Evidence grade AScope: Applies where natural and synthetic quartz must be distinguished; no self-administered criteria are given.
Sources G&G Summer 2014 · CIBJO Gemstone Book 2022
Other research findings
Quartz has the chemical composition SiO2 with traces of other elements.
Evidence grade BScope: Applies to the composition of the quartz species; inclusions aside.
Sources Handbook of Mineralogy
Cristobalite, tridymite, coesite and stishovite are polymorphs of quartz; quartz is stable below 573 C.
Evidence grade BScope: States the polymorph relationships and stability range; no synthesis claim.
Sources Handbook of Mineralogy
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- This record covers only the quartz species in general; colour varieties are treated in their own records.
- Green-quartz genesis and iris-quartz mechanism come from different GIA papers with different scopes.
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
- Quartz
GB/T 16552—2017 5.1.1 b) · IMA Mineral List 2026-07 “Quartz”
Construction or treatment status
Natural identity; treatment status unknown
Treatments recorded for this material: Heated / Heat-treated, Irradiated (via parent material), Filled / Fracture-filled (via parent material), Dyed (via parent material), Coated (via parent material)
Related:Disclosure and cautions
This page cannot answer
Natural? · Origin · Price
A lab report settles these; this wiki covers naming and disclosure.
Related:What this page can answer
Answer at a glance
Quartz is often subjected to heating. Under GB/T 16552-2017, heating counts as an optimization, so the plain gem name may be used (§5.4.2.1 a). Do not assume it is unenhanced.
Evidence
- GB/T · 5.1.1 b)
What this means for you
Before buying, check the recommended listing name "Quartz" and any disclosed treatments on this page, and ask the seller for a grading report if in doubt.
Known uncertainty
- See “Disclosure and cautions” above
- Disclosure rules for the treatments above can change as authorities update their standards; re-check before relying on this page.
- Last reviewed
- 2026-09-01
Care and wear
Normal care for every gemstone (CIBJO Gemstone Book §6.1), in brief:
- Handle it gently.
- Store pieces apart when not worn, so they cannot scratch each other.
- Clean with warm soapy water and a soft brush.
- Use ultrasonic cleaners only with caution.
The §6.1 wording and the full list of §6.2 special-care letters cited on this page are on the general gem care page.
Care
care (cleaning)2 sources compared
Quartz — care (cleaning): transparent quartz other than amethyst and citrine: ultrasonic and steamer: use caution; note: avoid thermal shock.
Gems & Gemology 1987 (Martin)
- Treatment state
- untreated
Source & check 2026-09-26
- Source
- Martin, “Gemstone Durability: Design to Display”, Gems & Gemology, Summer 1987: pp.66–67 fold-out chart, Quartz (other transparent varieties) row, CLEANING column (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quartz — care (cleaning): Some stones are susceptible to damage from ultrasonic cleaning. Do not expose them to ultrasonic cleaning.
CIBJO Gemstone Book 2022
CIBJO Gemstone Book §6.2:special-care code j
- Treatment state
- treated
- Applies only to
- iris quartz
Source & check 2026-09-26
- Source
- CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §8 Annex C, Iris Quartz, p.69-70; §6.2 j (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quartz — care (light): may fade or revert to its original colour in strong light; do not wear or leave it in strong light for extended periods.
CIBJO Gemstone Book 2022
CIBJO Gemstone Book §6.2:special-care code f
- Treatment state
- treated
- Only after these treatments
- irradiation
- Applies only to
- other colours, sold under a colour prefix
Source & check 2026-09-26
- Source
- Fact checked on
- 2026-09-26
Quartz — care (chemicals): Treatments with dye, oil, resin, wax or plastic are not permanent; keep it away from all solvents (including dish-washing liquids), chemicals and heat.
CIBJO Gemstone Book 2022
CIBJO Gemstone Book §6.2:special-care code k
- Treatment state
- treated
- Only after these treatments
- dyeing
- Applies only to
- iris quartz
Source & check 2026-09-26
- Source
- CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §8 Annex C, Iris Quartz, p.69-70; §6.2 k (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quartz — care (setting): transparent quartz other than amethyst and citrine: prong and bezel: relatively safe; flush, channel and pavé: avoid; note: may be included or fractured.
Gems & Gemology 1987 (Martin)
- Treatment state
- untreated
Source & check 2026-09-26
- Source
- Martin, “Gemstone Durability: Design to Display”, Gems & Gemology, Summer 1987: pp.66–67 fold-out chart, Quartz (other transparent varieties) row, SETTING column (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quartz — care (repair): transparent quartz other than amethyst and citrine: polishing: use caution; jeweller's torch, pickle pot and thermal shock: avoid; note: avoid thermal shock, which may fracture it, and heat, which turns smoky quartz colourless.
Gems & Gemology 1987 (Martin)
- Treatment state
- untreated
Source & check 2026-09-26
- Source
- Martin, “Gemstone Durability: Design to Display”, Gems & Gemology, Summer 1987: pp.66–67 fold-out chart, Quartz (other transparent varieties) row, REPAIR column (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quartz — care (display): transparent quartz other than amethyst and citrine: heat in the display case, sunlight and artificial light: relatively safe.
Gems & Gemology 1987 (Martin)
- Treatment state
- untreated
Source & check 2026-09-26
- Source
- Martin, “Gemstone Durability: Design to Display”, Gems & Gemology, Summer 1987: pp.66–67 fold-out chart, Quartz (other transparent varieties) row, DISPLAY column (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.
Common care questions and matching entries
CleaningCleaning Quartz: Martin's Gemstone Durability: Design to Display states that for untreated transparent quartz other than amethyst and citrine, ultrasonic and steam cleaning call for caution and thermal shock should be avoided; CIBJO states that treated iris quartz (Iris Quartz) must not be cleaned ultrasonically. Repair, setting and display: the same Martin source states that for untreated transparent quartz other than amethyst and citrine, polishing calls for caution, and the torch, post-soldering pickling solution and thermal shock should all be avoided as the stone may crack, while smoky quartz fades to colourless when heated; prong and bezel settings are relatively safe, while tension, channel and pavé settings should be avoided; display-case heat, daylight and artificial light are relatively safe. Light: CIBJO states that treated Quartz, specifically irradiated Quartz of other colours named with a colour prefix, can fade or revert to the original colour in strong light, so it should not be worn or left in strong light for long periods. Chemicals: CIBJO states that for treated iris quartz, specifically dyed material, treatments such as waxing, dyeing, oiling, resin impregnation or plastic impregnation are all non-permanent, and it should be kept away from all solvents (including detergents), chemicals and high temperatures.
This table scrolls sideways on narrow screens.
Care entries by treatment state
The same entries grouped by the treatment state each applies to; each links to its full wording and source. Letters are CIBJO special-care codes, explained on the gemstone care page.
untreated
- transparent quartz other than amethyst and citrine: ultrasonic and steamer: use caution; note: avoid thermal shock
- transparent quartz other than amethyst and citrine: prong and bezel: relatively safe; flush, channel and pavé: avoid; note: may be included or fractured
- transparent quartz other than amethyst and citrine: polishing: use caution; jeweller's torch, pickle pot and thermal shock: avoid; note: avoid thermal shock, which may fracture it, and heat, which turns smoky quartz colourless
- transparent quartz other than amethyst and citrine: heat in the display case, sunlight and artificial light: relatively safe
treated
- iris quartz: care (cleaning) §6.2 j
treated (Only after these treatments: irradiation)
- other colours, sold under a colour prefix: may fade or revert to its original colour in strong light; do not wear or leave it in strong light for extended periods §6.2 f
treated (Only after these treatments: dyeing)
Durability and wearing
Numbers in curly braces, such as {111}, are crystallographic face symbols (Miller indices): each marks a set of crystal faces or cleavage planes. They are reproduced as written in the cited source.
Toughness
Brittle, tough when massive
Cleavage
Rare; imperfect cleavage on {1011}, {0111}, {1010} and others, with rhombohedral parting
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 | — | — |
| Irradiation | — | — | Optimization | — | — |
| Filling | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Dyeing | — | — | Treatment | — | — |
| Coating | — | — | Treatment | — | — |
“—” means the cited source gives no value for that item, not “none”. Source: GB/T 16552—2017 Table B.1 (row for Rock Crystal); 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
How lab reports word it
A general LMHC wording rule also covers Quartz (Information Sheet #8): see the LMHC rule “When colour authenticity cannot be determined”.
VerifyNames, standards, technical facts, clauses and sources
Names
Standard and listing namesThe GB/T 16552—2017 Chinese formal name for Quartz is quartz, from Table A.1, row for rock crystal; the mineralogical name is Quartz (SiO2), IMA mineral species; the suggested listing name is Quartz. Names in four languagesNames are given in four languages: Simplified Chinese, Traditional Chinese, English (Quartz) and Japanese (a katakana transliteration and a kanji name). Institution usageOn authority wording, this site has recorded only CIBJO's wording, Quartz, from the CIBJO Gemmological Laboratories Book 2024; the FTC text on file has no wording for this name, which has been checked; GIA and Gem-A are unchecked; bodies without a recorded wording show the entry's own English name, which does not represent their position. Japanese namesThe entry's own Japanese name is the katakana and kanji pair, and Japan's GSJ wording for it is not yet verified by this site.
- GSJ (Japan) formal name
- クォーツ／石英 (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 石英 (GB/T 16552—2017 Table A.1, row “Rock Crystal”)
- Mineralogical name
- Quartz (SiO2); IMA mineral species
Four-language names
- 简体中文
- 石英
- 繁體中文
- 石英
- English
- Quartz
- 日本語
- クォーツ／石英
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 species
- Mineral chemical class
- Silicates
- Construction or treatment status
- Natural identity; treatment status unknown
Treatments listed by standards
GB/T 16552-2017, Annex B, Table B.1
Under the “Rock Crystal” row of Table B.1: Heating Optimization; Irradiation Optimization; Filling Graded — see §5.4.1, Table 1; Dyeing Treatment; Coating Treatment. The full row, with the effect column, is on the Rock Crystal 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
This table scrolls sideways on narrow screens.
| Gem name | Species | Colour | Listed in the table | Notes |
|---|---|---|---|---|
| Parti-Coloured Quartz | Quartz | two or more colours | an untreated tier is listed | no dedicated entry on this site; shown on the broader entry |
JJA/AGL definitions and nomenclature (2025 revision), table of principal gem names, p.10
How to read the JJA/AGL table: see the Gem treatments page.
What it is and how it's identified
The composition (phase) of Quartz is quartz; its nomenclature status is IMA status A, approved by the IMA (a mineral species accepted after the IMA was set up in 1958). The source is the Quartz listing in the CIBJO Blue Book — Gemmological Laboratories Book (Gemmological Commission 2024-1).
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
Quartz — nomenclature status: IMA status A: approved (accepted by the IMA after it was set up in 1958).
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Quartz — composition (phase): quartz
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Durability
Quartz — Mohs hardness: 7
Handbook of Mineralogy
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 (Source: Handbook of Mineralogy); Corundum 9 (Source: GIA Gem Encyclopedia (care guide))
- Qualification
The source we cite gives a Mohs hardness but no figure for toughness or stability.
- General note
- hardness only, not durability
Source & check 2026-10-08
- Source
- Quartz: p. 1, Physical Properties (locator checked 2026-10-08)
- Fact checked on
- 2026-10-08
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Testing and market
The CIBJO laboratory protocol (Gemmological Laboratories Book 2024) requires particular checks on Quartz for synthetics, coating, irradiation, heating, dyeing and impregnation (quartzite). The note on testing methods in the CIBJO laboratory protocol is: the special optical effect is asterism, and immersion observation is carried out in water.
The tests the CIBJO laboratory protocol requires for this material, and what each method means, are in the protocol table on the laboratory testing page: §6.1.65.
How far testing can go
Quartz — what the CIBJO laboratory protocol says to watch for: synthetics, coatings, irradiation, heat treatment, dyed and impregnated (quartzite).
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- any treatment state
Source & check 2026-09-26
- Source
- Fact checked on
- 2026-09-26
Quartz — notes on test methods in the CIBJO laboratory protocol:
| Test method | What the protocol notes for it |
|---|---|
| Phenomena: | Star; |
| Immersion: | In water |
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- any treatment state
Source & check 2026-09-26
- Source
- 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.
Clause-level definitions
Quartz has a clause-level definition in its IMA Mineral List entry, under the term Quartz, with the content Quartz SiO2 A 1967 s.p.; the cross-check is against the RRUFF/IMA master mineral list (public domain data).
This table scrolls sideways on narrow screens.
| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Quartz | IMA Mineral List entry | Quartz SiO2 A 1967 s.p. | Cross-checked against the RRUFF/IMA master mineral list (public domain data). |
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
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 (Quartz) 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, Irradiated (via parent material), Filled / Fracture-filled (via parent material), Dyed (via parent material), Coated (via parent material) | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Quartz 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.