On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Trade name: colour / appearance variety · Natural identity; treatment status unknown
Chrome Tourmaline
Also known asChromium-dravite
A trade variety name for tourmaline coloured green by chromium; it must be confirmed that the green really comes from chromium, and both the cause of colour and any treatment must be tested. 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 Chrome Tourmaline 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 Chrome TourmalineHow far lab testing can go
- Treatments and enhancements of Chrome TourmalineThe enhancements and treatments the GB/T and JJA/AGL tables list
- Caring for and wearing Chrome TourmalineCleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Chrome TourmalineEach value with its source and check date
- Chrome Tourmaline 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?
- Listing and disclosing Chrome TourmalineThe listing name to use; what must be disclosed before sale
- Standard clauses that define Chrome TourmalineWhich 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
Chrome tourmaline is a commercial/trade name, mostly for intense green dravite–uvite mixtures. Its intense green is coloured by traces of chromium (Cr3+) and/or vanadium (V3+), a different mechanism from iron-derived green; but the name is unreliable—GIA notes that so-called chrome tourmaline is actually coloured mostly by vanadium, and material sold as chrome tourmaline is not always coloured by chromium. One locality instance of the mechanism is green trapiche tourmaline from Zambia, which spectroscopy and chemistry show is uvite coloured by a vanadium-related mechanism. The parent minerals (uvite, dravite) form in limestone altered by heat and pressure to marble.
Scope: Applies to explaining natural deep green dravite–uvite (chromium / vanadium-caused green) and its trade name; chromium / vanadium-caused green must be distinguished from iron-caused green, and colouration data from one locality must not be taken as the general case for all tourmaline.
Sources GIA Tourmaline Description
Where it forms
Dravite and uvite form in limestone altered by heat and pressure to marble, occurring as accessory minerals.
Sources GIA Tourmaline Description
The intense green arises from trace chromium/vanadium rather than iron, requiring a corresponding elemental source.
Sources GIA Tourmaline Description
How it forms, step by step
Calcium- and magnesium-rich host rock is metamorphosed under heat and pressure into marble, crystallising dravite–uvite.
Sources GIA Tourmaline Description
Traces of chromium and/or vanadium enter the lattice, producing rich greens rivaling tsavorite and even emerald.
Sources GIA Tourmaline Description
Dealers call the material “chrome tourmaline”, but the actual chromophore may be vanadium, so the name does not guarantee chromium colouring.
Sources GIA Tourmaline Description
Link to appearance
The intense green may be caused by chromium, by vanadium, or even by iron, and appearance cannot distinguish them; “chrome tourmaline” is a trade label and colour cannot fix the colouring element.
Sources GIA Tourmaline Description · G&G Spring 2007
Timescale
The cited sources give no absolute timescale for chrome tourmaline (dravite–uvite) formation.
Sources GIA Tourmaline Description
Related base materials
- Dravite–uvite (tourmaline group): trade name for intense green dravite–uvite tourmaline
Supporting findings
Uvite and dravite form in marble produced from limestone altered by heat and pressure, occurring as accessory minerals.
Evidence grade AScope: A setting statement for these tourmalines; it does not apply to green elbaite in pegmatites.
Sources GIA Tourmaline Description
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Africa
- Landanai, Manyara, TanzaniaTanzania is noted for fine chrome tourmaline; illustrated material is from Landanai; not stated as sole or main
Sources Gems & Gemology Summer 1992 · Gems & Gemology Spring 2007
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
Dravite–uvite mixtures carrying traces of vanadium, chromium, or both produce rich greens (rivalling tsavorite and even emerald), sold as “chrome tourmaline” even though not always coloured by chromium.
Evidence grade AScope: Concerns Cr/V green in dravite–uvite mixtures and must not be extended to all green tourmaline.
Sources GIA Tourmaline Description
Chromium (Cr3+)/vanadium (V3+) green differs from iron-derived colour: the same dravite–uvite system can be intense green from traces of V/Cr (chrome tourmaline) or bright yellow from iron (savannah tourmaline), colour depending on which trace element is present.
Evidence grade AScope: A synthesis of two source passages showing different trace elements give different colours in the same system; it is not a criterion for a single specimen.
Sources GIA Tourmaline Description
Green trapiche tourmaline from Zambia is uvite, shown by spectroscopy and chemistry to be coloured by a vanadium-related mechanism.
Evidence grade AScope: A mechanism for a single-locality (Zambia) sample; a locality-specific case not to be generalised to all chrome tourmaline or all tourmaline.
Sources G&G Spring 2007
Other research findings
Chrome tourmaline shows an intense green. Despite the name, vanadium — the very element responsible for the colour of many emeralds from Brazil and Africa — is what usually gives it its hue.
Evidence grade AScope: A general note on the trade name and its colouring; it does not guarantee chromium or vanadium colouring in any given specimen.
Sources GIA Tourmaline Description
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The cited sources give no absolute timescale for chrome tourmaline (dravite–uvite) formation.
- Cr/V-green sample data come mainly from specific localities (e.g. Zambia) and must not be generalised to all tourmaline.
- “Chrome tourmaline” is a trade name; the actual colouring element (chromium, vanadium, or both) requires laboratory testing.
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
- Chrome Tourmaline
16 CFR Part 23 §23.24 · CIBJO Gemmological Laboratories Book 2024 §7.2.1.54 “Chrome tourmaline”
Construction or treatment status
Natural identity; treatment status unknown
Treatments recorded for this material: Heated / Heat-treated (via parent material), Filled / Fracture-filled (via parent material), Dyed (via parent material), Irradiated (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
Chrome Tourmaline is Green chromium-bearing tourmaline trade variety; use "Chrome Tourmaline" for listings, and disclose any known treatments.
Evidence
What this means for you
Before buying, check the recommended listing name "Chrome Tourmaline" 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
The item-by-item care advice that the GIA Care and Cleaning Guide gives for the whole class, and so for Chrome Tourmaline, is set out in full under care on the Tourmaline entry.
Care
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
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 | — | — |
| Filling | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Dyeing | — | — | Treatment | — | — |
| Irradiation | — | — | 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 Tourmaline); 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
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Chrome Tourmaline, the name register records "Chromium-dravite", for which no restriction on use as a name is recorded.
Chinese standard nameThe national-standard name corresponding to Chrome Tourmaline is tourmaline (GB/T 16552—2017 Table A.1); the cited original does not list chrome tourmaline itself. Institution usageCIBJO records the English wording Chrome Tourmaline (CIBJO Gemmological Laboratories Book 2024); the FTC text on file has no wording for this name (checked); GIA and Gem-A are unchecked, and bodies without a recorded wording show the entry's own English name, which does not represent their position. Japanese namesThe Japanese name is a katakana transliteration, and Japan's GSJ wording is not yet verified by this site. Trade and mineralogical namesThe mineralogical name is a trade variety name for chromium-bearing green tourmaline, and the trade name/synonym is Chromium-dravite. Names in four languagesNames are given in four languages: Simplified Chinese, Traditional Chinese, English (Chrome Tourmaline) and Japanese (katakana). Recommended listing nameThe suggested listing name is Chrome Tourmaline.
Name register
Every name recorded for this entry, with how it is classified, whether it may be matched to this entry automatically, whether it may be used as a product name, and the clause it rests on.
This table scrolls sideways on narrow screens.
| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (1) | ||||
| Chromium-draviteEnglish | synonym | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- クロムトルマリン (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)
- 碧玺 (GB/T 16552—2017 Table A.1)
- Mineralogical name
- Green chromium-bearing tourmaline trade variety
- Trade names and synonyms
- Chromium-dravite (synonym)
Four-language names
- 简体中文
- 铬碧玺
- 繁體中文
- 鉻碧璽
- English
- Chrome Tourmaline
- 日本語
- クロムトルマリン
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Tourmaline-supergroup minerals and gem varieties
- Identity tier
- Trade name: colour / appearance variety
- 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 “Tourmaline” row of Table B.1: Heating Optimization; Filling Graded — see §5.4.1, Table 1; Dyeing Treatment; Irradiation Treatment; Coating Treatment. The full row, with the effect column, is on the Tourmaline 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 |
|---|---|---|---|---|
| Chrome Tourmaline | Tourmaline | green (chromium) | an untreated tier is listed |
JJA/AGL definitions and nomenclature (2025 revision), table of principal gem names, p.15
How to read the JJA/AGL table: see the Gem treatments page.
What it is and how it's identified
The composition (phase) of Chrome Tourmaline is chrome tourmaline (tourmaline group). Under the clause for tourmaline (the whole mineral group), Chrome Tourmaline is crystalline, trigonal, with rounded trigonal prismatic or ditrigonal pyramidal-prismatic crystals and pronounced longitudinal striations on the crystal faces; Mohs hardness 7–8, cleavage none; density 2.46–3.26 g/cm³, derived from the clause value 3.06 and its permitted tolerance (+0.20, −0.60); refractive index 1.615–1.655, derived from the clause value 1.624–1.644 and its permitted tolerance (+0.011, −0.009); birefringence 0.018–0.04, where this site uses the overall value and the clause has finer sub-ranges; optical character anisotropic, uniaxial, negative; the cat's-eye effect can occur, and the colour-change effect can occur but is rare. Untreated, under the clause for tourmaline (the whole mineral group), pleochroism is moderate to strong, in darker and lighter shades of the body colour, and lustre is vitreous. The body colour of Chrome Tourmaline is bluish green to slightly yellowish or brownish green, treatment status untreated; the site notes that chapter 7 of the CIBJO Gemmological Laboratories Book also uses green or greenish colours for entries such as variscite, kornerupine and chrysoberyl.
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”.
Luminescence, UV-visible spectrum, infrared spectrum, magnification: these whole-class features are given in the cited clause for tourmaline (the whole mineral group), so they are not repeated on the Chrome Tourmaline page; see the material facts on the Tourmaline entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Chrome Tourmaline (how to read class-level values).
Definition
Chrome Tourmaline — nomenclature status: IMA status Rd: redefined (a mineral already known, given a new definition in the IMA era).
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Chrome Tourmaline — composition (phase): chromium-dravite (tourmaline group)
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Structure
Chrome Tourmaline — structure (overall): crystalline
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — structure (crystal system): trigonal
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — structure (crystal habit): rounded trigonal prisms or more complex ditrigonal prism-and-pyramid combinations; the crystal faces are distinctly striated lengthwise.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Chrome Tourmaline — Mohs hardness: 7–8
GB/T 16553—2017
Reference points on this site: Talc 1–3, Fluorite 4, Apatite 5–5.5, Orthoclase 6–6.5, Topaz 8, Diamond 10 (Source: GB/T 16553—2017); Gypsum 1.5–2, Calcite 3, Quartz 7 (Source: Handbook of Mineralogy); Corundum 9 (Source: GIA Gem Encyclopedia (care guide))
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Chrome Tourmaline — cleavage: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Chrome Tourmaline — density: 2.46–3.26 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
- Qualification
The clause we cite gives 3.06, with a stated tolerance of +0.20 / -0.60. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Optical
Chrome Tourmaline — optic character: uniaxial, optically negative (anisotropic)
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — refractive index: 1.615–1.655
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
- Qualification
The clause we cite gives 1.624–1.644, with a stated tolerance of +0.011 / -0.009. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Chrome Tourmaline — birefringence: 0.018–0.04
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
- General note
- the clause has finer ranges
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Chrome Tourmaline — pleochroism: moderate to strong, in lighter and deeper shades of the body colour.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — optical effect (chatoyancy): seen
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — optical effect (colour change): seen; rare
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Chrome Tourmaline — body colour: bluish green to slightly yellowish or brownish green.
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- untreated
- Qualification
In chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of Variscite, Kornerupine, Chrysoberyl and other entries also name green or a greenish colour.
- General note
- colour alone is not identity
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
- CIBJO definitions
- chatoyancy, colour change
Quality factors
Chrome Tourmaline — quality factor (lustre): vitreous
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- tourmaline (the whole mineral group)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.10 (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): 1.635 / 2.86; Closest values: 1Prehnite 1.625 / 2.88, 2Larimar 1.62 / 2.82, 3Datolite 1.646 / 2.95, 4Danburite 1.633 / 3, 5Sugilite 1.61 / 2.77
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
Testing and market
The CIBJO laboratory protocol covers Chrome Tourmaline under “Tourmaline” (§6.1.86): see identification on the Tourmaline entry; the required tests are listed on the CIBJO laboratory protocol table for Tourmaline.
How far testing can go
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Clause-level definitions
Chrome Tourmaline is defined directly in CIBJO Gemmological Laboratories Book 2024, with the registered term Chrome tourmaline. The definition given in CIBJO Gemmological Laboratories Book 2024 is: mineral group tourmaline, mineral species chromium-dravite, IMA status Rd, trade name chrome tourmaline, 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.
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| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Chrome tourmaline | 7.2.1.54 | bluish green to slightly yellowish or brownish green chromium-dravite Colour due to chromium and/or vanadium | Defined directly by CIBJO; no identically named English entry was found in this edition of the GB/T annex. |
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.
- GIA – Gemological Institute of America (United States). Gem Encyclopedia.
- Gem-A – The Gemmological Association of Great Britain (United Kingdom).
- eCFR (United States). 16 CFR § 23.24 — Disclosure of treatments to gemstones. In: 16 CFR Part 23 — Guides for the Jewelry, Precious Metals, and Pewter Industries.
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 Tourmaline on this site: 12 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Chrome Tourmaline) is marked.
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Tourmaline-supergroup minerals and gem varieties | Live |
| Treatments recorded for this material | Heated / Heat-treated (via parent material), Filled / Fracture-filled (via parent material), Dyed (via parent material), Irradiated (via parent material), Coated (via parent material) | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Chrome Tourmaline 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.