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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
Vesuvianite / Idocrase
Also known asCalifornite · Idocrase
A mineral species listed in GB/T 16552-2017 Appendix A.1 as Idocrase; Idocrase is a traditional synonym, and Californite is a trade variety of it. 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 Vesuvianite / Idocrase forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- How to identify Vesuvianite / IdocraseHow far lab testing can go
- Caring for and wearing Vesuvianite / IdocraseCleaning, heat, chemicals and light, as the cited sources give them; durability indicators and wearing advice
- Hardness, density and refractive index of Vesuvianite / IdocraseEach value with its source and check date
- Vesuvianite / Idocrase in English, Chinese and Japanese; national standard namesNames in four languages, the GB/T standard name and the suggested listing name; and: Has any of GIA, FTC, CIBJO or Gem-A put a name for it on record here?
- Name origin and history of Vesuvianite / IdocraseWhere the name comes from
- Listing and disclosing Vesuvianite / IdocraseThe listing name to use; what must be disclosed before sale
- Standard clauses that define Vesuvianite / IdocraseWhich 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
Vesuvianite—known commercially as idocrase—is a calcium aluminium (magnesium, iron) silicate of complex composition. It is found chiefly in skarns that developed where limestones underwent contact or regional metamorphism, and also in garnetized gabbros, mafic and ultramafic rocks and serpentinites, being uncommon in alkalic igneous rocks. Grossular, diopside, wollastonite, epidote, scapolite, spinel and calcite are its usual companions, and its crystals are morphologically intricate, with roughly thirty forms reported on a single crystal.
Scope: Applies to the genesis, composition and occurrence of vesuvianite as a complex calc-silicate mineral species of skarn type, including the boundary of the synonym idocrase; does not cover synthetic materials.
Sources Handbook of Mineralogy · CIBJO Gemstone Book 2022
Where it forms
Skarns formed by contact or regional metamorphism of limestones
Sources Handbook of Mineralogy
Garnetized gabbros, mafic and ultramafic rocks, and serpentinites
Sources Handbook of Mineralogy
Uncommon in alkalic igneous rocks
Sources Handbook of Mineralogy
How it forms, step by step
Limestones interact with Al-, Si-, Mg- and Fe-bearing fluids/melts at intrusive contacts or during regional metamorphism.
Sources Handbook of Mineralogy
During skarn-forming reactions, vesuvianite crystallizes together with grossular, diopside, wollastonite, epidote and others.
Sources Handbook of Mineralogy
The resulting crystals are morphologically complex, with up to about thirty forms reported on a single crystal.
Sources Handbook of Mineralogy
Crystals range from short pyramidal to long prismatic, or form columnar, granular and massive aggregates.
Sources Handbook of Mineralogy
Link to appearance
Vesuvianite may be yellow, green or brown, also colorless to white, blue, violet, bluish green, pink, red or black, commonly zoned, with a vitreous to resinous luster.
Sources Handbook of Mineralogy
Timescale
The sources state no timescale for vesuvianite formation.
Sources Handbook of Mineralogy · CIBJO Gemstone Book 2022
Supporting findings
Vesuvianite occurs chiefly in skarns formed by contact or regional metamorphism of limestones, and also in garnetized gabbros, mafic-ultramafic rocks and serpentinites, and is uncommon in alkalic igneous rocks.
Evidence grade BScope: Describes vesuvianite's occurrence environment; not the sole origin of any one locality.
Sources Handbook of Mineralogy
Vesuvianite is commonly associated with grossular, diopside, wollastonite, epidote, scapolite, spinel and calcite.
Evidence grade BScope: Describes common vesuvianite associations; not every locality contains all of these minerals.
Sources Handbook of Mineralogy
Vesuvianite crystals are morphologically complex, with up to about thirty forms reported on a single crystal.
Evidence grade BScope: Describes vesuvianite's crystal growth morphology; not laboratory synthesis.
Sources Handbook of Mineralogy
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Europe
- Mount Somma, Naples, Campania, Italy
Sources Mindat: Vesuvianite · Handbook of Mineralogy
Seas and coasts
- WorldwideGood crystals worldwide; Mindat lists 1,796 localities
Sources Handbook of Mineralogy · Mindat: Vesuvianite
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
The English name vesuvianite is derived from its occurrence at Vesuvius, Italy.
Evidence grade BScope: Etymology explains the origin of the name only; it does not establish the material's composition, locality, naturalness, or treatment.
Sources Handbook of Mineralogy
Other research findings
Vesuvianite's trade synonym is idocrase; CIBJO lists Vesuvianite and Idocrase as two names for the same material.
Evidence grade AScope: Defines the synonym relationship between vesuvianite and idocrase; it does not treat idocrase as an independent material.
Sources CIBJO Gemstone Book 2022
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The sources state no absolute geological timescale for vesuvianite formation.
- Vesuvianite is compositionally complex with several substitutions; this record gives no complete chemical formula.
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
- Vesuvianite (idocrase)
GB/T 16552—2017 Table A.1 “Idocrase” · IMA Mineral List 2026-07 “Vesuvianite”
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
Vesuvianite / Idocrase is Vesuvianite; use "Vesuvianite (idocrase)" for listings, and disclose any known treatments.
Evidence
- GB/T · Table A.1, row 符山石 (Vesuvianite / Idocrase)
What this means for you
Before buying, check the recommended listing name "Vesuvianite (idocrase)" 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
Vesuvianite / Idocrase — 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, Vesuvianite, p.86; §6.2 j (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
CleaningCan Vesuvianite / Idocrase go in an ultrasonic cleaner? The care entry for Vesuvianite in the CIBJO Gemstone Book (2022, Coloured Stone Commission) states that it must not be cleaned ultrasonically, and the entry is marked as applying to any treatment state. General careGeneral care that applies to all gems, and the full table of special care letters cited in each entry, are in the general care section of the material entries index page.
This table scrolls sideways on narrow screens.
| Question | Matching entries |
|---|---|
| Can it go in an ultrasonic or steam cleaner? | care (cleaning) |
Durability and wearing
Toughness
Brittle
Fracture
Subconchoidal to irregular
Sources Handbook of Mineralogy
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Vesuvianite / Idocrase, the name register records "Californite" and "Idocrase", for which no restriction on use as a name is recorded (CIBJO Gemmological Laboratories Book 2024 §7.2.1.38 “Californite”; CIBJO Gemstone Book 2022 Annex 8 “Californite”).
Standard and listing namesThe Chinese formal name for Vesuvianite / Idocrase is given in GB/T 16552—2017 Table A.1, and the suggested listing name is also Vesuvianite. Trade and mineralogical namesThe mineralogical name is Vesuvianite, and the trade name or synonym is Idocrase. Sub-names and unacceptable namesCalifornite is a subordinate name (variety or subtype), registered from the CIBJO Gemmological Laboratories Book 2024 and the CIBJO Gemstone Book 2022, with no restriction on its use as a name recorded; Idocrase is a synonym based on this site's ruling, without a supporting clause. Names in four languagesThe names are given in Simplified Chinese, Traditional Chinese, English (Vesuvianite / Idocrase) and Japanese (a kanji-katakana name and a transliteration); the Japanese names are the entry's own, and the Japanese GSJ wording for them is not yet verified by this site. Institution usageThe wordings of GIA, FTC, CIBJO and Gem-A for Vesuvianite / Idocrase are not yet verified by this site; Vesuvianite / Idocrase is the entry's own English name and does not represent the position of the four bodies.
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.
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| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (2) | ||||
| CaliforniteEnglish | narrower name (variety or subtype) | matched automatically | no restriction recorded | CIBJO Gemmological Laboratories Book 2024 §7.2.1.38 “Californite”; CIBJO Gemstone Book 2022 Annex 8 “Californite” |
| IdocraseEnglish | 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
- ベスブ石／ベスビアナイト (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 符山石 (GB/T 16552—2017 Table A.1)
- Mineralogical name
- Vesuvianite
- Trade names and synonyms
- Idocrase (synonym) · Californite (narrower name (variety or subtype))
Four-language names
- 简体中文
- 符山石
- 繁體中文
- 符山石
- English
- Vesuvianite / Idocrase
- 日本語
- ベスブ石／ベスビアナイト
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
The registered material facts for Vesuvianite / Idocrase are: composition Ca10Mg2Al4(SiO4)5(Si2O7)2(OH)4, which may contain Cu, Fe and other elements; the structure is crystalline and tetragonal, with a prismatic crystal habit, or compact, massive granular or prismatic aggregates; Mohs hardness 6–7, with imperfect cleavage that is generally not seen in aggregates. This site notes that hardness alone is not enough to judge durability. Density is 3.25–3.5 g/cm³, the cited clause giving 3.40 with a tolerance of +0.10/−0.15, from which the limits are derived. The optic character is anisotropic, uniaxial positive or negative, or that of an anisotropic aggregate; refractive index is 1.7–1.721, the cited clause giving 1.713–1.718 with a tolerance of +0.003/−0.013, from which the limits are derived; this site notes that the cited clauses for refractive index and birefringence have further sub-grades, and the overall values are registered. Birefringence is 0.001–0.012; transparency is transparent to translucent; in the untreated state, the quality factor (lustre) is vitreous.
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
Vesuvianite / Idocrase — composition (chemistry): Ca10Mg2Al4 (SiO4) 5 (Si2O7) 2 (OH) 4, elements such as Cu and Fe may be contained.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Structure
Vesuvianite / Idocrase — structure (overall): crystalline
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — structure (crystal system): tetragonal
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — structure (crystal habit): columnar, or compact massive granular or columnar aggregates.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Durability
Vesuvianite / Idocrase — Mohs hardness: 6–7
GB/T 16553—2017
Reference points on this site: Talc 1–3, Fluorite 4, Apatite 5–5.5, Orthoclase 6–6.5, Topaz 8, Diamond 10 (Source: GB/T 16553—2017); Gypsum 1.5–2, Calcite 3, Quartz 7 (Source: Handbook of Mineralogy); Corundum 9 (Source: GIA Gem Encyclopedia (care guide))
- Does this standard apply
- applies to this entry
- General note
- hardness only, not durability
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — cleavage: imperfect in single crystals; aggregates usually show none.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Physical properties
Vesuvianite / Idocrase — density: 3.25–3.5 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- Qualification
The clause we cite gives 3.40, with a stated tolerance of +0.10 / -0.15. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Optical
Vesuvianite / Idocrase — optic character: uniaxial with a positive or negative sign (anisotropic), or an anisotropic aggregate.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — refractive index: 1.7–1.721
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- Qualification
The clause we cite gives 1.713–1.718, with a stated tolerance of +0.003 / -0.013. The range shown here is worked out from that.
- General note
- the clause has finer ranges
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — birefringence: 0.001–0.012
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- General note
- the clause has finer ranges
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — transparency: transparent, translucent.
CIBJO Gemmological Laboratories Book 2024
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Vesuvianite / Idocrase — pleochroism: none to weak, depending on color; not measurable on aggregates.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — fluorescence (overall): none
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — spectrum (UV-visible): 464 nm absorption peak; 528.5 nm weak absorption peak.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — spectrum (infrared): Idocrase's own diagnostic absorption bands appear in the mid-IR
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Vesuvianite / Idocrase — magnification: gas-liquid inclusions, mineral inclusions, granular or columnar structure aggregate.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
body colour2 sources compared
Vesuvianite / Idocrase — body colour: Yellowish green, green, yellowish brown, violet.
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- untreated
- Qualification
In chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of Chrysoberyl, Peridot, Andalusite and other entries also name green or a greenish colour.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- Fact checked on
- 2026-09-26
Vesuvianite / Idocrase — body colour: yellow-green, brown-yellow, pale blue to green-blue, grey, white and others; spotty color is common.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- Qualification
In chapter 5 of GB/T 16553—2017, the colour entries of Nephrite, Hemimorphite, Chrysoberyl and other variety clauses also name green or a greenish colour.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
How the sources relate
- CIBJO Gemmological Laboratories Book 2024 and GB/T 16553—2017
Both list yellowish green and yellowish brown (GB/T 16553—2017 says brownish yellow). GB/T 16553—2017 also lists light blue to greenish blue, grey and white and notes that spotty colour patches are common; the CIBJO Gemmological Laboratories Book also lists green and violet.
Quality factors
Vesuvianite / Idocrase — quality factor (lustre): vitreous
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.1.31 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
This material (RI / SG midpoints): 1.711 / 3.38; Closest values: 1Hydrogrossular 1.7 / 3.35, 2Enstatite 1.712 / 3.31, 3Tanzanite 1.696 / 3.28, 4Epidote 1.737 / 3.38, 5Fei Cui / Jadeite Jade 1.683 / 3.35
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 tests the CIBJO laboratory protocol requires for this material, and what each method means, are in the protocol table on the laboratory testing page: §6.1.42.
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
The clause-level definitions for Vesuvianite / Idocrase in the CIBJO Gemmological Laboratories Book 2024 are registered separately under Californite, Idocrase and Vesuvianite. Californite is defined as green to yellowish green or brownish green, often with grey or white spots or veining, translucent to opaque, massive; the cross-check is a direct CIBJO definition, and no identically named English entry was found in this edition of the GB/T annex. The definitions of Idocrase and Vesuvianite both give the mineral species as vesuvianite, IMA status A, with the CIBJO wording quoted in full under Clause-level definitions on this page; the cross-check for Idocrase is a direct CIBJO definition that also appears in the GB/T annex, and for Vesuvianite a direct CIBJO definition with no identically named English entry found in this edition of the GB/T annex.
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| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Californite | 7.2.1.38 | Green to yellowish or brownish green, often mottled or veined with grey or white; translucent to opaque, massive | Defined directly by CIBJO; no identically named English entry was found in this edition of the GB/T annex. |
| Idocrase | 7.2.1.113 | In the trade, idocrase is used as synonym for vesuvianite. Yellowish green, green, yellowish brown, violet; transparent, translucent | Defined directly by CIBJO; also present in the GB/T annex. |
| Vesuvianite | 7.2.1.259 | Yellowish green, green, yellowish brown, violet; transparent, translucent | 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.
- 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 Vesuvianite / Idocrase 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.