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UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Mineral species · Natural identity; treatment status unknown
Pyrophyllite
A common matrix mineral in Chinese carving stones and a component mineral of the national standard's "clay minerals jade". It is an IMA mineral species in its own right and is not suitable as a product name on its own. 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 Pyrophyllite forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- How to identify PyrophylliteHow far lab testing can go and whether a synthetic exists
- Caring for and wearing PyrophylliteCleaning, heat, chemicals and light, as the cited sources give them; durability indicators and wearing advice
- Mohs hardness of PyrophylliteEach value with its source and check date
- Pyrophyllite 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 PyrophylliteWhere the name comes from
- Listing and disclosing PyrophylliteThe listing name to use; what must be disclosed before sale
- Standard clauses that define PyrophylliteWhich 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
Pyrophyllite, formula Al2Si4O10(OH)2, is an aluminium sheet silicate. It is relatively uncommon, appearing within hydrothermal veins and in bedded deposits hosted by schistose metamorphic rocks. It is commonly found alongside kyanite, andalusite, topaz, mica and quartz — an assemblage that points to low- to medium-grade metamorphic and hydrothermal conditions. Its name derives from the Greek words for fire and leaf, referring to its habit of exfoliating into fan-like shapes when heated.
Scope: Applies to the genesis, composition, occurrence and appearance of pyrophyllite as a natural aluminous layer silicate mineral species; does not cover synthetic materials or products such as carving stones.
Sources RRUFF Pyrophyllite
Where it forms
Veins of hydrothermal origin.
Sources RRUFF Pyrophyllite
Deposits occurring as beds within schistose metamorphic rocks.
Sources RRUFF Pyrophyllite
Metamorphic-hydrothermal settings associated with kyanite, andalusite, topaz, mica and quartz
Sources RRUFF Pyrophyllite
How it forms, step by step
Aluminium-rich rocks or sediments undergo low- to medium-grade metamorphism or hydrothermal activity.
Sources RRUFF Pyrophyllite
Bedded pyrophyllite deposits form within schistose metamorphic rocks.
Sources RRUFF Pyrophyllite
Hydrothermal fluids precipitate pyrophyllite along fractures, forming hydrothermal veins.
Sources RRUFF Pyrophyllite
Pyrophyllite crystallizes with kyanite, andalusite, topaz, mica and quartz.
Sources RRUFF Pyrophyllite
Link to appearance
Pyrophyllite is white, pale blue, yellow, apple-green, grayish green or brownish green (colorless in thin section), with a pearly to dull luster; it occurs as lamellar crystals, or as spherulitic aggregates of radiating needle-like crystals, fine-grained foliated or massive.
Sources RRUFF Pyrophyllite
Timescale
The source states no absolute geological timescale for pyrophyllite formation.
Sources RRUFF Pyrophyllite
Supporting findings
Pyrophyllite is relatively uncommon, appearing within hydrothermal veins and in bedded deposits hosted by schistose metamorphic rocks.
Evidence grade BScope: Describes pyrophyllite's hydrothermal and metamorphic occurrence; not other settings.
Sources RRUFF Pyrophyllite
Pyrophyllite is commonly associated with kyanite, andalusite, topaz, mica and quartz.
Evidence grade BScope: Describes pyrophyllite's typical assemblage, indicating low- to medium-grade metamorphic-hydrothermal settings; not all localities share it.
Sources RRUFF Pyrophyllite
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Asia
- Nagano Prefecture, JapanSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
Europe
- Krassik, between Pyshma and Berezovsky, Ural Mountains, RussiaSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- St. Niklaus, Zermatt, Valais, SwitzerlandSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- Västanå, Kristianstad, SwedenSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- near Ottré, Ardennes, BelgiumSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
North America
- Ogilby, Tres Cerritos and Champion mine (White Mountains), California, United StatesSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- Near Quartzsite, La Paz County, Arizona, United StatesSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- Staley, Glendon, Robbins and Hillsborough, North Carolina, United StatesSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- Brewer mine, Chesterfield County, South Carolina, United StatesSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
- Graves Mountain, Lincoln County, Georgia, United StatesSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
South America
- Ibitiara, Bahia, BrazilSpecimen/occurrence locality listed by the Handbook of Mineralogy; not a commercial gem source
Sources RRUFF Pyrophyllite
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.
Where the name comes from
Pyrophyllite's name joins Greek words for fire and leaf, alluding to how it tends to exfoliate into fan shapes on heating.
Evidence grade BScope: The etymology explains the origin of a name only; it does not attest composition, locality, naturalness or treatment.
Sources RRUFF Pyrophyllite
Other research findings
Pyrophyllite has the formula Al2Si4O10(OH)2 and is an aluminium sheet-silicate mineral.
Evidence grade BScope: Describes pyrophyllite's composition and structural type; not industrial grading.
Sources RRUFF Pyrophyllite
The name pyrophyllite comes from the Greek for fire and leaf, alluding to its tendency to exfoliate into fan shapes when heated.
Evidence grade BScope: Concerns the origin of the mineral's name, not its geological formation.
Sources RRUFF Pyrophyllite
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The source states no absolute geological timescale for pyrophyllite formation.
- The source does not quantify the specific P-T conditions of pyrophyllite formation and hydrothermal precipitation.
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
- Pyrophyllite
GB/T 16552—2017 5.1.1 b) · IMA Mineral List 2026-07 “Pyrophyllite”
Construction or treatment status
Natural identity; treatment status unknown
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
Pyrophyllite is Pyrophyllite (IMA mineral species); use "Pyrophyllite" for listings, and disclose any known treatments.
Evidence
- GB/T · 5.1.1 b)
What this means for you
Before buying, check the recommended listing name "Pyrophyllite" and any disclosed treatments on this page, and ask the seller for a grading report if in doubt.
Known uncertainty
- Last reviewed
- 2026-09-01
Care and wear
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
Pyrophyllite — 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
- any treatment state
Source & check 2026-09-25
- Source
- CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §8 Annex C, Pyrophyllite, p.68; §6.2 j (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Pyrophyllite — care (wear): Some stones are prone to scratching due to low hardness. Wear them with care.
CIBJO Gemstone Book 2022
CIBJO Gemstone Book §6.2:special-care code a
- Treatment state
- any treatment state
Source & check 2026-09-25
- Source
- CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §8 Annex C, Pyrophyllite, p.68; §6.2 a (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
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
CleaningCare conclusions for Pyrophyllite are registered from the CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022): it must not be cleaned ultrasonically; it is soft and scratches easily, so wear it with care. Both the care (cleaning) and care (wear) entries apply whatever the treatment state. General careGeneral care that applies to all gemstones, and the complete list of CIBJO special-care letter codes, are in the general care section of the materials index page.
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| Question | Matching entries |
|---|---|
| Can it go in an ultrasonic or steam cleaner? | care (cleaning) |
| Wearing limits (knocks, settings) | care (wear) |
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.
Mohs hardness
1–2
Toughness
Flexible but inelastic
VerifyNames, standards, technical facts, clauses and sources
Names
Trade and mineralogical namesThe mineralogical name of Pyrophyllite is Pyrophyllite, an IMA mineral species. Names in four languagesThe four-language names are the Simplified and Traditional Chinese names, English Pyrophyllite and the Japanese names. Standard and listing namesThe Chinese formal name corresponds to Pyrophyllite, citing the “Chicken-blood stone” row of GB/T 16552—2017 Table A.2; the suggested listing name is Pyrophyllite, based on GB/T 16552—2017 and Pyrophyllite in the IMA mineral list 2026-07. Institution usageFor authority wording, CIBJO records Pyrophyllite (CIBJO Gemmological Laboratories Book 2024); the FTC text on file has no wording for this name (checked); GIA and Gem-A are unchecked, and the English name shown for bodies without a recorded wording is Pyrophyllite's own name, which does not represent their position. Japanese namesThe Japanese names shown are the entry's own, and GSJ's wording for this name is not yet verified by this site.
- GSJ (Japan) formal name
- パイロフィライト／葉蝋石 (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 叶蜡石 (GB/T 16552—2017 Table A.2, row “Chicken-blood Stone”)
- Mineralogical name
- Pyrophyllite (IMA mineral species)
Four-language names
- 简体中文
- 叶蜡石
- 繁體中文
- 葉蠟石
- English
- Pyrophyllite
- 日本語
- パイロフィライト／葉蝋石
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Other silicate minerals
- Identity tier
- Mineral species
- Mineral chemical class
- Silicates
- Construction or treatment status
- Natural identity; treatment status unknown
What it is and how it's identified
Among the registered material facts for Pyrophyllite, the nomenclature status is IMA status G: grandfathered, meaning described before the IMA existed and generally regarded as a valid mineral species; the composition (phase) is pyrophyllite. Optically, the transparency of Pyrophyllite is translucent to opaque; for untreated Pyrophyllite, the body colour is registered as white, pale yellow, green or blue. The site's supplementary note explains that in chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of entries such as amazonite, common opal and larimar also include white or whitish tones; colour alone is not enough to establish identity or natural origin.
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
Pyrophyllite — nomenclature status: IMA status G: grandfathered (described before the IMA existed, and generally regarded as a valid species).
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Pyrophyllite — composition (phase): pyrophyllite
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Optical
Pyrophyllite — transparency: translucent, opaque.
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Pyrophyllite — body colour: White, pale yellow, green or blue.
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- untreated
- Qualification
In chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of Amazonite, Common Opal, Larimar and other entries also name white or a whitish colour.
- General note
- colour alone is not identity
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Testing and market
The conclusion registered for Pyrophyllite on identification and market is that there is no synthetic pyrophyllite on the market. The source for whether synthetics are on the market is the Pyrophyllite entry in the CIBJO Gemstone Book (2022), with code N.
How far testing can go
Pyrophyllite — synthetic counterpart on the market: No synthetic counterpart of this material is commercially available
CIBJO Gemstone Book 2022
- Treatment state
- any treatment state
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Clause-level definitions
Pyrophyllite is defined directly in CIBJO Gemmological Laboratories Book 2024 under the term Pyrophyllite, giving the mineral species as pyrophyllite and the IMA status as G, with the CIBJO wording quoted in full under Clause-level definitions on this page; the cross-check shows it is defined directly by CIBJO, and no identically named English entry was found in this edition of the GB/T annex. Pyrophyllite is registered in the IMA Mineral List entry as Pyrophyllite Al2Si4O10(OH)2, cross-checked against the RRUFF/IMA master mineral list on the basis of public domain data.
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| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Pyrophyllite | 7.2.1.189 | White, pale yellow, green or blue, translucent, opaque; compact spherulitic aggregates of acicular radiating crystals or massive | Defined directly by CIBJO; no identically named English entry was found in this edition of the GB/T annex. |
| Pyrophyllite | IMA Mineral List entry | Pyrophyllite Al2Si4O10(OH)2 G 1829 | 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.
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| Page | Content | Status |
|---|---|---|
| Browsing family | Other silicate minerals | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Pyrophyllite 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.