On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural organic and biogenic materials · Organic or biogenic material · Natural identity; treatment status unknown
Pink Coral
Also known asAngel skin coral (not to be used as a name) · Bello (conditional name) · Bianco Rosa · Boké (conditional name) · Magai (conditional name) · Midway (conditional name) · Peau d'Ange (conditional name) · Pelle d'Angello (conditional name) · Rosato
A pink variety of Precious Coral, found among the varieties listed in CIBJO Coral Blue Book 2024 §5.78; natural colour and dyed colour must be noted separately. Also known as Bello, Boké. 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 Pink Coral 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 Pink CoralIdentification points from the research literature; how far lab testing can go
- Treatments and enhancements of Pink Coral2 registered treatments: status, stability, how common they are and identification leads
- Caring for and wearing Pink CoralCleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Pink CoralEach value with its source and check date
- Pink Coral 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 Pink CoralHow people have used it, with museum objects
- Listing and disclosing Pink CoralThe listing name to use; what must be disclosed before sale
- Standard clauses that define Pink CoralWhich 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
Pink coral is the collective designation of the pink-toned varieties of precious coral (family Corallidae), corresponding to commercial names of several species: 'Midway / Rosato / White-Pink' refers to Pleurocorallium secundum, giving red-spotted or veined, or uniformly clear-pink, pink/white coral; 'Cerasuolo / Momo / Satsuma' refers to Pleurocorallium elatius, bright red to salmon, orange, dark pink and flesh-coloured with a lengthwise white 'soul'. As a precious coral, pink coral forms a skeleton of biomineralised calcium carbonate secreted by deep-water polyps; its trade status follows that of precious coral (the Corallidae group being listed in CITES Appendix III at China's request).
Scope: Applies to an overview of the definition, occurrence and composition of pink coral as a collective term for the pink-toned varieties of precious coral; different trade names correspond to different species.
Sources CIBJO Coral Blue Book 2024 · CITES Checklist
Where it forms
Deep-water, low-light rocky sea beds (the shared setting of precious corals).
Sources CIBJO Coral Blue Book 2024
The Pacific (e.g. P. secundum near Hawaii) and seas near Japan and Taiwan (P. elatius).
Sources CIBJO Coral Blue Book 2024
How it forms, step by step
Polyps of the genus Pleurocorallium live colonially in deep water.
Sources CIBJO Coral Blue Book 2024
The polyps secrete biomineralised calcium carbonate, forming branched hard skeletons.
Sources CIBJO Coral Blue Book 2024
Different species and portions produce clear pink, red-spotted, to bright red/salmon-orange pink tones, giving several pink-coral commercial names.
Sources CIBJO Coral Blue Book 2024
As a precious coral, it is managed in trade under the rules for the Corallidae group.
Sources CIBJO Coral Blue Book 2024 · CITES Checklist
Link to appearance
Pink coral is clear pink, pink-white with red spots, or bright red, salmon, orange, dark pink and flesh-coloured with a lengthwise white 'soul'; it has a porcelain-like lustre when polished.
Sources CIBJO Coral Blue Book 2024
Timescale
No authoritative growth-rate figure was available, so no timescale is stated.
Sources CIBJO Coral Blue Book 2024
Related base materials
- Precious coral: Collective name to which pink coral belongs
- Pleurocorallium elatius: Species corresponding to pink trade names such as Cerasuolo/Momo
- Pleurocorallium secundum: Species corresponding to pinkish-white trade names such as Midway/Rosato
Supporting findings
Pink coral is a deep-water colonial coral whose polyps secrete a biomineralised calcium carbonate hard skeleton.
Evidence grade AScope: Describes its biological origin; no specific chemical values.
Sources CIBJO Coral Blue Book 2024
Recorded localities
This is an organic material; its localities are the harvest or culture areas (waters or species ranges) recorded by authoritative sources.
Seas and coasts
- Midway seamountsP. secundum, 400–600 m.
Sources CIBJO Coral Blue Book 2024
- Waters off Hawaii, United StatesP. secundum, 400–600 m.
Sources CIBJO Coral Blue Book 2024
- Waters off JapanP. elatius, 150–350 m.
Sources CIBJO Coral Blue Book 2024
- Waters off Taiwan, ChinaP. elatius, 150–350 m.
Sources CIBJO Coral Blue Book 2024
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
'Cerasuolo / Momo / Satsuma' (Pleurocorallium elatius) is bright red, salmon, orange, dark pink and flesh-coloured with a lengthwise white 'soul'; 'Midway / Rosato' (Pleurocorallium secundum) is red-spotted or veined pink-white or uniform clear pink.
Evidence grade AScope: Describes colour traits of the commercial names; no quantitative pigment data.
Sources CIBJO Coral Blue Book 2024
Human use and museum objects
Coral objects in museum holdings date after the 16th century and continue into the modern era, e.g. a Peruvian coral necklace before 1532 (Cleveland Museum of Art, 1940.499) and a Qing Mandarin necklace (Cleveland Museum of Art, 1952.472); neither colour nor species is recorded, so pink coral cannot be confirmed.
Evidence grade AScope: Evidence belongs to the precious-coral parent material behind pink coral; colour is unrecorded and no pink-coral-specific claim is made.
Sources Cleveland Museum of Art 1940.499 · The Met 2009.300.2984a–c
Museum objects identified as coral cluster after the 16th century and extend into the modern era. Earlier pieces include a Peruvian coral necklace before 1532 (Cleveland Museum of Art, 1940.499), a 1704 chasuble with accessories (The Met, 2009.300.2984a–c) and a statue robe of ca. 1690–1720 (The Met, 43.164); the rest are largely 18th–20th century works such as a Qing Mandarin necklace (Cleveland Museum of Art, 1952.472), an Algerian silver-set coral necklace (The Met, 55.111.56) and a Nepalese nose ring (Cleveland Museum of Art, 1916.290). Museum records mostly say only 'coral', specifying neither species nor colour, so these pieces cannot be confirmed as pink coral; the evidence belongs to the precious-coral parent material behind pink coral and is not exclusive to the name 'pink coral'.
Sources Cleveland Museum of Art 1940.499 · The Met 2009.300.2984a–c
Scope: Museum objects attest only to the existence and date of the individual documented pieces; they do not evidence widespread ancient use of the material, nor the origin, naturalness or treatment of any modern specimen.
Objects cited
- Cleveland Museum of Art 1940.499coral
- The Met 2009.300.2984a–cSilk, linen, coral, metal, jet
- The Met 43.164Metal thread, coral beads
- Cleveland Museum of Art 1952.472jade and coral beads, pendants mounted in gold and enamel
- The Met 55.111.56Silver, enamel, coral
- Cleveland Museum of Art 1916.290silver, gilded; turquoise, coral and red glass
How it is identified
Pink coral colour can resemble other corals, dyed carbonates, or plastic imitations, and the eye cannot readily separate natural colour from dyed or imitation products. Judging the colour cause and material identity depends on laboratory testing such as microscopic structural examination and spectroscopic instruments; the cited nomenclature sources give no self-test criteria, and conclusions must be issued by an accredited laboratory.
Evidence grade AScope: Colour and appearance are insufficient; determination requires testing by an accredited laboratory, and this entry provides no threshold.
Sources CIBJO Coral Blue Book 2024
Other research findings
Pink coral is the collective designation of the pink-toned varieties of precious coral; 'Midway / Rosato / White-Pink' refers to Pleurocorallium secundum and 'Cerasuolo / Momo / Satsuma' to Pleurocorallium elatius.
Evidence grade AScope: Defines the commercial names and their species; not a separate species.
Sources CIBJO Coral Blue Book 2024
CITES does not list the whole coral family Coralliidae: only four species — Corallium japonicum, Pleurocorallium elatius, P. konojoi and P. secundum — are in Appendix III at China's request (effective 01/07/2008). Whether a pink coral is covered depends on which species it is.
Evidence grade AScope: Defines the trade-control level; no judgement on source legality.
Sources CIBJO Coral Blue Book 2024 · CITES Checklist
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- Pink coral is a collective of pink-toned precious-coral varieties, not a separate species; different commercial names map to different species.
- Note the level is CITES Appendix III (at China's request).
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
- Pink Coral (state the genus, species and any treatments)
GB/T 16552—2017 Table A.3 “Coral” · CIBJO Coral Blue Book 2024 §5.78, §5.28, §5.4, Annex C §7.6
Construction or treatment status
Natural identity; treatment status unknown
Treatments recorded for this material: Waxed, Impregnated, Bleached (via parent material), Filled / Fracture-filled (via parent material), Coated (via parent material), Dyed
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
Pink Coral is often subjected to waxing and impregnation.
Under GB/T 16552-2017, waxing (not listed separately in GB/T; Table 1 groups it with colourless oil or wax filling) counts as an optimization, so the plain gem name may be used (§5.4.2.1 a); impregnation is graded by the material used, and must be stated in the name wherever it counts as a treatment (§5.4.1, Table 1). Do not assume it is unenhanced.
Evidence
- CIBJO · 5.78
What this means for you
Before buying, check the recommended listing name "Pink Coral (state the genus, species and any treatments)" and any disclosed treatments on this page, and ask the seller for a grading report if in doubt.
Known uncertainty
- This entry's exact material identity is not fully settled.
- See “Disclosure and cautions” above
- 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
Trade-name ruling
- Laboratory identification required before the name is used.
- Suggested listing name
- Pink Coral (state the genus, species and any treatments)
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.
The normal care that applies to all corals, and so to Pink Coral (CIBJO Coral Book §6.1), and the special care the source gives for some corals without saying which ones (§6.2), are set out in full under care on the Coral entry.
Care
Pink Coral — 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, Pink Coral, p.41; §6.2 j (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Pink Coral — care (chemicals): porous, so do not let it come into contact with coloured fluids; particularly susceptible to attack by acids, so keep it away from acids.
CIBJO Gemstone Book 2022
CIBJO Gemstone Book §6.2:special-care code c, special-care code h
- 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, Pink Coral, p.41; §6.2 c, h (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Pink Coral — 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
Source & check 2026-09-25
- Source
- CIBJO Blue Book — Official Gemstone Book (Coloured Stone Commission 2022) (CIBJO): §8 Annex C, Pink Coral, p.41; §6.2 k (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Pink Coral — 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, Pink Coral, p.41; §6.2 a (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Pink Coral — care (special care): assembled with polymers and dyed: special care (SC); avoid chemicals and solvents.
AGTA Gemstone Information Manual, 17th ed.
- Treatment state
- treated
- Only after these treatments
- dyeing, impregnation
Source & check 2026-09-26
- Source
- AGTA Gemstone Information Manual, 17th edition (August 2026) (AGTA): p.IX, Gemstone Information Chart, Coral Pink D,I, CARE REQUIRED / SPECIAL ADVICE (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
CleaningPink Coral must not be cleaned ultrasonically, in any treatment state; the source is CIBJO (The World Jewellery Confederation). ChemicalsCIBJO (The World Jewellery Confederation) also states that, in any treatment state, Pink Coral is porous, should not come into contact with coloured liquids, is particularly sensitive to acids and must be kept away from them. For treated Pink Coral, where the treatment is dyeing, oiling, resin impregnation, waxing or plastic impregnation, the effect is not permanent, and all solvents (detergents included), chemicals and heat must be avoided. Special careThe 17th edition of the AGTA Gemstone Information Manual states that, for dyed or impregnated Pink Coral only, material assembled with polymer and dyed needs special care (marked SC) and should be kept away from chemicals and solvents. WearCIBJO (The World Jewellery Confederation) further states that, in any treatment state, Pink Coral is soft and scratches easily, so it should be worn with care.
This table scrolls sideways on narrow screens.
| Question | Matching entries |
|---|---|
| Can it go in an ultrasonic or steam cleaner? | care (cleaning) |
| Contact with acids, alkalis and household chemicals | porous, so do not let it come into contact with coloured fluids; particularly susceptible to attack by acids, so keep it away from acids; Treatments with dye, oil, resin, wax or plastic are not permanent; keep it away from all solvents (including dish-washing liquids), chemicals and heat |
| Wearing limits (knocks, settings) | care (wear) |
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.
any treatment state
- care (cleaning) §6.2 j
- porous, so do not let it come into contact with coloured fluids; particularly susceptible to attack by acids, so keep it away from acids §6.2 c, h
- care (wear) §6.2 a
treated
treated (Only after these treatments: dyeing, impregnation)
Treatments and identification leads
Registered treatmentsThe treatments recorded for Pink Coral are surface waxing and impregnation. Stability and frequencySurface waxing has the status treated, stability not stable and prevalence common; impregnation has the status treated, stability not stable and prevalence common. Values not givenThe identification leads and source for both surface waxing and impregnation are shown as “—”, meaning the cited source gives no value, not “none”. Registered treatmentsThe recorded treatments, their stability and prevalence, and the identification leads for each treatment are intended for use when submitting stones for testing and discussing which tests to run.
This table scrolls sideways on narrow screens.
| Treatment | Market frequency (CIBJO) | Stability (CIBJO) | GB/T 16552 category | JJA/AGL listing | Identification leads |
|---|---|---|---|---|---|
| surface waxingStatus: treated | commonly | unstable | — | — | — |
| impregnationStatus: treated | commonly | unstable | — | — | — |
| Bleaching | — | — | Optimization | — | — |
| Filling | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Coating | — | — | Graded — see §5.4.1, Table 1 | — | — |
| Dyeing | — | — | Treatment | — | — |
| colouring (including coloured wax) | — | — | — | colouring (including coloured wax) | — |
Where each treatment acts (schematics): Waxed · Impregnated
“—” means the cited source gives no value for that item, not “none”. Source: CIBJO Gemstone Book 2022; GB/T 16552—2017 Table B.1 (row for Coral); 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
For Pink Coral, "Bello", "Bianco Rosa", "Boké", "Magai", "Midway", "Peau d'Ange", "Pelle d'Angello" and "Rosato" are recorded with no restriction on use as a name, while "Angel skin coral" must not be used as a name (16 CFR Part 23 §23.1; CIBJO Coral Blue Book 2024 §5.4).
Standard and listing namesThe suggested listing name for Pink Coral is Pink Coral (state genus/species and treatment). The national-standard counterpart is coral (GB/T 16552—2017 Table A.3), and the original standard does not list Pink Coral. Trade and mineralogical namesThe mineralogical name is Pink precious coral (CIBJO Annex C). Sub-names and unacceptable namesThe trade name/synonym Angel skin coral, in the CIBJO Coral Blue Book 2024, refers to an extremely rare, albino, unusually pale pink precious coral; it is not a generic name, is kept as a search term only, is not matched to Pink Coral and must not be used as a name. Names in four languagesNames are given in Simplified Chinese, Traditional Chinese, English (Pink Coral) and Japanese. Institution usageOn authority wording, no wording for this name can be found in the FTC text (checked); the wording of GIA, CIBJO and Gem-A is unchecked, and the English name shown for bodies without a recorded wording comes from the entry itself and does not represent their position. Japanese namesThe wording used by GSJ (Japan) is not yet verified by this site, and the entry's own Japanese name is shown. Trade and mineralogical namesAmong the other registered market names, Bianco Rosa and Rosato may be matched automatically; Bello, Boké, Magai, Peau d'Ange and Pelle d'Angello are matched only once the condition is confirmed; and Midway is a search candidate only.
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 (8) | ||||
| BelloEnglish | market name | matched only once the condition is confirmed | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Bello” |
| Bianco RosaEnglish | market name | matched automatically | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Bianco Rosa” |
| BokéEnglish | market name | matched only once the condition is confirmed | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Boké” |
| MagaiEnglish | market name | matched only once the condition is confirmed | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Magai” |
| MidwayEnglish | market name | search candidate only | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Midway” |
| Peau d'AngeEnglish | market name | matched only once the condition is confirmed | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Peau d’Ange” |
| Pelle d'AngelloEnglish | market name | matched only once the condition is confirmed | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Pelle d’Angello” |
| RosatoEnglish | market name | matched automatically | no restriction recorded | CIBJO Coral Blue Book 2024 Annex C 7.7 “Rosato” |
| not to be used as a name (1) | ||||
| Angel skin coralEnglish | market name | never matched to this entry | not to be used as a name | 16 CFR Part 23 §23.1; CIBJO Coral Blue Book 2024 §5.4; Note: Angel skin refers only to a very rare, albino pale-pink precious coral, not to pink coral in general. Matching it to this entry would merge two materials of very different value, and using it for ordinary pink coral misstates the grade. |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- 桃色珊瑚 (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)
- 珊瑚 (GB/T 16552—2017 Table A.3)
- Mineralogical name
- Pink precious coral (CIBJO Annex C)
- Trade names and synonyms
- Bello (market name; conditional name) · Boké (market name; conditional name) · Magai (market name; conditional name) · Peau d'Ange (market name; conditional name) · Pelle d'Angello (market name; conditional name) · Bianco Rosa (market name) · Midway (market name; conditional name) · Rosato (market name)Not to be used as a name: Angel skin coral (market name)
Four-language names
- 简体中文
- 粉珊瑚
- 繁體中文
- 粉珊瑚
- English
- Pink Coral
- 日本語
- 桃色珊瑚
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural organic and biogenic materials
- Browsing family
- Coral materials
- Identity tier
- Organic or biogenic material
- Mineral chemical class
- Not applicable
- Construction or treatment status
- Natural identity; treatment status unknown
Treatments listed by standards
GB/T Table B.1Pink Coral is classified by applying the coral row of GB/T 16552—2017 Annex B Table B.1: bleaching is listed as an enhancement; filling and coating are both noted as following the grading rules; dyeing is listed as a treatment. The notes to Table B.1 and the definitions of each grade are on the treatments page. JJA/AGL designationsThe Japanese JJA/AGL table lists Coral under the species coral, in pink and red, with the treatment listed as colouring, noted as including coloured wax, with dyeing and waxing in parentheses; a note states that the JJA/AGL entry is listed under Coral, and the original does not name pink coral.
GB/T 16552-2017, Annex B, Table B.1
Under the “Coral” row of Table B.1: Bleaching Optimization; Filling Graded — see §5.4.1, Table 1; Coating Graded — see §5.4.1, Table 1; Dyeing Treatment. The full row, with the effect column, is on the Coral 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
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| Gem name | Species | Colour | Listed in the table | Notes |
|---|---|---|---|---|
| Coral | Coral | pink, red | colouring (including coloured wax) (Dyed, Waxed) | listed under “Coral” in the table; this page is related (the source does not name it) |
JJA/AGL definitions and nomenclature (2025 revision), table of principal gem names, p.13
How to read the JJA/AGL table: see the Gem treatments page.
What it is and how it's identified
The material facts for Pink Coral are registered for the class ranges in the cited clause; they are not measurements of Pink Coral itself. Registered for coral as a whole (calcareous and horny): the structure of calcareous coral is a cryptocrystalline aggregate in its inorganic part and amorphous in its organic part, while horny coral is amorphous; cleavage usually not seen in an aggregate; optic character aggregate; untreated Pink Coral has the quality factor (lustre) waxy, vitreous on polished surfaces. Registered for calcareous coral: Mohs hardness 3–4.5; the stability of untreated Pink Coral is that it effervesces with a drop of hydrochloric acid; density 2.6–2.7 g/cm³, with the limits derived from the cited clause value of 2.65 and its stated tolerance of ±0.05; refractive index 1.48–1.66, which the cited clause gives as a reading often obtained by the spot method, a common value rather than an absolute limit.
Registered material facts
Each row carries its own source and check date and can be cited on its own; “—” means the cited source gives no value, not “none”.
Chemical composition, luminescence, UV-visible spectrum, infrared spectrum, magnification: these whole-class features are given in the cited clause for calcareous coral, coral as a whole (calcareous and horny), so they are not repeated on the Pink Coral page; see the material facts on the Coral entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Pink Coral (how to read class-level values).
Structure
Pink Coral — structure (overall): calcareous coral: the inorganic part is a cryptocrystalline aggregate and the organic part is non-crystalline. Horny coral: non-crystalline.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- coral as a whole (calcareous and horny)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Pink Coral — Mohs hardness: 3–4.5
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
- calcareous coral
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Pink Coral — cleavage: generally not seen on an aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- coral as a whole (calcareous and horny)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Pink Coral — stability: effervesces on contact with hydrochloric acid
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- calcareous coral
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
For Pink Coral, the stability of surface waxing is “unstable”.
CIBJO Gemstone Book 2022
- Treatment state
- treated
- Treatment
- surface waxing
- Qualification
This says how well the treatment holds up, not how durable Pink Coral itself is.
- General note
- no durability verdict here
Source & check 2026-09-25
- Source
- Fact checked on
- 2026-09-25
For Pink Coral, the stability of impregnation is “unstable”.
CIBJO Gemstone Book 2022
- Treatment state
- treated
- Treatment
- impregnation
- Qualification
This says how well the treatment holds up, not how durable Pink Coral itself is.
- General note
- no durability verdict here
Source & check 2026-09-25
- Source
- Fact checked on
- 2026-09-25
Physical properties
Pink Coral — density: 2.6–2.7 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- calcareous coral
- Qualification
The clause we cite gives 2.65, with a stated tolerance of ±0.05. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Optical
Pink Coral — optic character: aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- coral as a whole (calcareous and horny)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Pink Coral — refractive index: 1.48–1.66
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- calcareous coral
- Qualification
The clause we cite gives this as a value commonly read by the spot (distant-vision) method. It is a common value, not an absolute limit.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Pink Coral — pleochroism: not measurable on an aggregate
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- coral as a whole (calcareous and horny)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quality factors
Pink Coral — quality factor (lustre): waxy; polished surfaces take a vitreous lustre.
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- coral as a whole (calcareous and horny)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.4 (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): 1.57 / 2.65; Closest values: 1Scapolite 1.558 / 2.67, 2Changhua Stone 1.56 / 2.6, 3Amethyst 1.548 / 2.67, 4Balin Stone 1.56 / 2.55, 5Qingtian Stone 1.565 / 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 identification of Pink Coral is registered under the CIBJO laboratory protocol (Blue Book laboratory volume, 2024): the protocol covers Pink Coral under Coral, so for the identification of Pink Coral see the identification part of the Coral entry, and the list of required tests is on the laboratory testing page. Among the registered findings for Pink Coral in trade, surface waxing occurs commonly and impregnation occurs commonly; both treatments are registered with the status treated.
The CIBJO laboratory protocol covers Pink Coral under “Coral” (§6.2.4): see identification on the Coral entry; the required tests are listed on the CIBJO laboratory protocol table for Coral.
How far testing can go
For Pink Coral in trade, the reported frequency of surface waxing is “commonly”.
CIBJO Gemstone Book 2022
- Treatment state
- treated
- Treatment
- surface waxing
Source & check 2026-09-25
- Source
- Fact checked on
- 2026-09-25
For Pink Coral in trade, the reported frequency of impregnation is “commonly”.
CIBJO Gemstone Book 2022
- Treatment state
- treated
- Treatment
- impregnation
Source & check 2026-09-25
- Source
- 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.
Clause-level definitions
The clause-level definition of Pink Coral is registered in GB/T 16552—2017 Annex A under the term Pink Coral. The registered definition is itself a pointer: the full description is in the original CIBJO Coral Blue Book 2024, and it notes that the name registered in GB/T 16552—2017 Table A.3 is coral. The cross-check result is that it is listed directly in GB/T, and no identically titled standalone entry was found in CIBJO.
This table scrolls sideways on narrow screens.
| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Pink Coral | GB/T 16552-2017 Annex A | For the full description, see Annex C §7.6 in CIBJO Coral Blue Book 2024; Table A.3 “Coral” in GB/T 16552—2017. | Listed directly by GB/T; CIBJO carries no standalone entry under the same name. |
Evidence and sources
Authority basis and clause sources
Sources
- CIBJO – The World Jewellery Confederation. Gemmological Laboratories Book (Blue Book), Gemmological Commission 2024-1.
- CIBJO – The World Jewellery Confederation. The Gemstone Book (Blue Book), 2022.
- SAMR / SAC (China). GB/T 16552—2017 Gems — Nomenclature.
- 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.
- CITES Secretariat. Appendices I, II and III, valid from 5 March 2026.
- CIBJO – The World Jewellery Confederation. The Coral Book (Blue Book), 2024.
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 Coral 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 (Pink Coral) is marked.
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Coral materials | Live |
| Treatments recorded for this material | Waxed, Impregnated, Bleached (via parent material), Filled / Fracture-filled (via parent material), Coated (via parent material), Dyed | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Pink Coral 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.