On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural organic and biogenic materials · Organic or biogenic material · Cultured formation; treatments recorded separately
Saltwater Cultured Pearl
Also known asAkoya/Tahitian/South Sea cultured pearl (conditional name) · Cortez cultured pearl (annotation only, never as the product name) · Dobo pearls (annotation only, never as the product name) · Fiji cultured pearl (annotation only, never as the product name) · Gulf cultured pearl (annotation only, never as the product name) · Saltwater Pearl (conditional name) · Sango cultured pearl (conditional name)
A cultured pearl formed with human intervention inside a saltwater mollusc; under GB/T it may be shortened to "saltwater pearl". Also known as Akoya/Tahitian/South Sea cultured pearl, Sango cultured pearl. 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 Saltwater Cultured Pearl forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- How to identify Saltwater Cultured PearlIdentification points from the research literature
- Treatments and enhancements of Saltwater Cultured PearlThe enhancements and treatments the GB/T and JJA/AGL tables list
- Caring for and wearing Saltwater Cultured PearlCleaning, heat, chemicals and light, as the cited sources give them
- Hardness, density and refractive index of Saltwater Cultured PearlEach value with its source and check date
- Saltwater Cultured Pearl 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?
- Listing and disclosing Saltwater Cultured PearlThe listing name to use; what must be disclosed before sale
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
Layers, outside to centre:
- nacre
- shell bead nucleus
Saltwater cultured pearls are grown in marine mollusks — pearl oysters of the genus Pinctada — through human seeding and tissue transplantation. Typically, a piece of mantle tissue (saibo) is removed from a donor mollusk and implanted, with a shell bead nucleus, inside the gonad of a host oyster; the grafted epithelium cells multiply and join, creating a pearl sac around the bead, which secretes nacre inward, layer by layer, until a beaded saltwater cultured pearl forms. The donor tissue is the main factor in the colour and nacre thickness; P. maxima usually needs a growth period of at least two years to yield thick nacre.
Scope: Covers the origin of bead-nucleated saltwater cultured pearls through bead insertion plus tissue grafting, the pearl-sac deposition mechanism and the role of the donor tissue; does not apply to non-beaded pearls or the freshwater culturing pathway.
Sources G&G Spring 2013 · G&G Fall 2021 · CIBJO Pearl Book 2024
- Gemological Characteristics of Saltwater Cultured Pearls Produced After Xenotransplantation (Gems & Gemology, Spring 2013, Vol. 49, No. 1)
- Internal Structures of Known Pinctada maxima Pearls: Cultured Pearls from Operated Marine Mollusks (Gems & Gemology, Fall 2021, Vol. 57, No. 3)
- CIBJO Pearl Book 2024 (Pearl Commission) — Blue Book
Where it forms
Gonad of the host pearl oyster: the site where the bead and donor tissue form a pearl sac and deposit nacre.
Sources G&G Fall 2021 · GIA Pearl Description
Saltwater farms: between the Tropic of Cancer and the Tropic of Capricorn, coinciding with the native Pinctada distribution.
Sources G&G Fall 2021 · GIA Pearl Description
How it forms, step by step
A piece of mantle tissue (saibo) is taken from a donor oyster and a shell bead nucleus is prepared.
The bead nucleus together with donor tissue is inserted into the host oyster's gonad (the seeding or nucleation process).
Grafted epithelium cells form a pearl sac surrounding the bead nucleus.
The pearl sac secretes nacre inward, depositing layer upon layer onto the bead surface to form a beaded saltwater cultured pearl.
Link to appearance
Nacre thickness and color are governed jointly by the donor tissue and the host's growth rate; P. maxima yields white to silver and golden pearls while P. margaritifera commonly yields dark gray to black, so appearance differs markedly with host/donor combination.
Sources G&G Spring 2013 · GIA Pearl Description
Timescale
P. maxima usually needs a growth period of at least two years to produce cultured pearls with the thickest nacre; the actual time depends on the species and the farming conditions.
Sources G&G Fall 2021
Related base materials
- Marine pearl oyster (Pinctada spp., e.g. P. maxima, P. margaritifera, P. fucata): biogenic-host | Saltwater cultured pearls form inside molluscs of the genus Pinctada
- Shell bead nucleus (freshwater mussel shell): inserted-nucleus | Beaded saltwater cultured pearls deposit nacre around a shell nucleus
Supporting findings
Most saltwater cultured pearls are produced by transplanting a piece of mantle tissue (saibo) and implanting it, with a shell bead nucleus, inside the host oyster's gonad.
Evidence grade AScope: The standard culturing path for beaded saltwater cultured pearls.
Grafted epithelium cells multiply and link to form a pearl sac around the bead nucleus, then deposit nacre inward to form the pearl; the sac derives from human-implanted tissue.
Evidence grade AScope: Pearl sac formation and deposition mechanism, from Pinctada maxima cultured pearl research.
The donor tissue largely determines the color and nacre thickness of saltwater cultured pearls; P. maxima and P. margaritifera differ in growth rate, affecting nacre deposition.
Evidence grade AScope: From xenotransplantation experiments; applies to the role of Pinctada donor tissue.
P. maxima generally requires a minimum two-year growth period and yields cultured pearls with the thickest nacre; pearls from this mollusk are often called 'South Sea'.
Evidence grade AScope: The growth period and market term for P. maxima; not a timescale for all saltwater cultured pearls.
Recorded localities
This is an organic material; its localities are the harvest or culture areas (waters or species ranges) recorded by authoritative sources.
Asia
- JapanSaltwater; akoya
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- ChinaSaltwater; akoya, P. maxima and P. margaritifera
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- VietnamSaltwater
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- IndonesiaSaltwater; akoya and South Sea
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- PhilippinesSaltwater; South Sea (Pinctada maxima)
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- MyanmarSaltwater; Pinctada maxima since 1957
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- ThailandSaltwater
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
North America
- Guaymas, Sonora, MexicoSaltwater; rainbow-lipped oyster since 2000
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
Oceania
- AustraliaSaltwater; South Sea (Pinctada maxima)
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- French PolynesiaSaltwater; major producer of Pinctada margaritifera (Tahiti cultured pearl)
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
- Cook IslandsSaltwater; Pinctada margaritifera
Sources CIBJO Pearl Book 2024
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1)
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 the origin determination guide and the overview of recorded localities.
How it is identified
Saltwater cultured pearls look similar to natural saltwater or freshwater cultured pearls, so distinguishing them relies on testing rather than looks. Using routine gemological tests with UV-Vis reflectance spectroscopy, real-time X-radiography and X-ray fluorescence, and by measuring nacre thickness, a laboratory can assess the culture method and host mollusk; the final verdict should be issued by an accredited body.
Evidence grade AScope: Deciding saltwater culture status is done in a laboratory with a report; no self-service criteria are given.
Sources GIA: How GIA Identifies Pearls
Other research findings
Saltwater cultured pearls can be assessed by real-time microradiography to measure nacre thickness, used to judge whether nacre appears thin.
Evidence grade AScope: A laboratory identification method; distinct from the formation account.
Sources GIA: How GIA Identifies Pearls
CIBJO defines a saltwater cultured pearl as one produced by a saltwater mollusc, and it stipulates that 'saltwater cultured pearl' may be used only of cultured pearls grown in saltwater bodies.
Evidence grade AScope: The naming definition (clause 5.173) plus trade-term rule (clause 4.5.1.3); defines the name by its saltwater host.
Sources CIBJO Pearl Book 2024
Saltwater cultured pearls are assessed by lustre, nacre thickness, surface, shape, colour and matching, consistent with GIA's seven Pearl Value Factors. Bead-nucleated saltwater cultured pearls (such as South Sea, Tahitian and Akoya) are cultured around a bead, and nacre thickness is a measurable factor tied to the culturing period and affecting colour, lustre and durability, but thickness does not equal nacre quality. Compared with freshwater cultured pearls the emphasis differs: bead-cultured saltwater pearls weigh nacre thickness, while most freshwater pearls are beadless and the nacre-thickness measure usually does not apply. Imitation pearls are not subject to pearl quality assessment.
Evidence grade AScope: Quality factors describe which characteristics the market generally prizes; they are not a grade for any specific specimen and are neither price nor investment advice. Pearl quality assessment must be issued by an accredited laboratory for a specific specimen.
Sources CIBJO Pearl Book 2024 · GIA: How GIA Identifies Pearls
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- Sources mainly discuss beaded saltwater cultured pearls; non-beaded (keshi-type) marine pearls belong to other records.
- Growth time varies by locality and species; only the two-year minimum for P. maxima is given.
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
- Saltwater Cultured Pearl (state the type)
GB/T 16552—2017 Table A.3 “Saltwater Cultured Pearl”, 5.1.2.3 b)
Construction or treatment status
Cultured formation; treatments recorded separately
Treatments recorded for this material: Bleached (via parent material), Dyed (via parent material), Irradiated (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
"Saltwater Cultured Pearl" is a market name rather than a mineral species name; before using it, verify: Laboratory identification required before the name is used.
What this means for you
Before buying, check the recommended listing name "Saltwater Cultured Pearl (state the type)" 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
- Last reviewed
- 2026-09-01
Trade-name ruling
- Laboratory identification required before the name is used.
- Suggested listing name
- Saltwater Cultured Pearl (state the type)
Care and wear
The normal and special care that applies to all natural and cultured pearls, and so to Saltwater Cultured Pearl (CIBJO Pearl Book §7.1, §7.2; the source says this advice counts as normal across the whole range and should be passed on to the buyer), is set out in full under care on the Pearl entry.
Care
Saltwater Cultured Pearl — care (light): may fade or revert to its original colour, so it should not be left for long periods in strong natural or artificial light or under strong display lighting.
CIBJO Pearl Book 2024
- Treatment state
- treated
- Only after these treatments
- coating, dyeing
Source & check 2026-09-26
- Source
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) (CIBJO): §8.2 Annex C, Saltwater Cultured Pearl, p.54; §7.2, §7.2.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — care (wear): breaks easily, so it is not meant for everyday wear and should not be worn during heavy work.
CIBJO Pearl Book 2024
- Treatment state
- treated
- Only after these treatments
- filling
Source & check 2026-09-26
- Source
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) (CIBJO): §8.2 Annex C, Saltwater Cultured Pearl, p.54; §7.2, §7.2.1 (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
For the care of Saltwater Cultured Pearl, the CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) records that treated pearls, and only those that are coated or dyed, may fade or revert to their original colour in light and should not be left for long periods in strong natural light, strong artificial light or strong display lighting; treated pearls, and only those that are filled, break easily, are not meant for everyday wear and should not be worn during heavy physical work. The general and specific care for all natural and cultured pearls also applies to Saltwater Cultured Pearl and is listed in full in the care part of the Pearl entry; the CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) says that the general and specific care advice should be treated as standard for all pearls and passed on to the buyer.
This table scrolls sideways on narrow screens.
| Question | Matching entries |
|---|---|
| Light and display | may fade or revert to its original colour, so it should not be left for long periods in strong natural or artificial light or under strong display lighting |
| Wearing limits (knocks, settings) | breaks easily, so it is not meant for everyday wear and should not be worn during heavy work |
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.
treated (Only after these treatments: coating, dyeing)
treated (Only after these treatments: filling)
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 |
|---|---|---|---|---|---|
| Bleaching | — | — | Optimization | — | — |
| Dyeing | — | — | Treatment | — | — |
| Irradiation | — | — | Treatment | — | — |
“—” means the cited source gives no value for that item, not “none”. Source: GB/T 16552—2017 Table B.1 (row for Cultured Pearl)
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
VerifyNames, standards, technical facts, clauses and sources
Names
For Saltwater Cultured Pearl, "Akoya/Tahitian/South Sea cultured pearl", "Saltwater Pearl" and "Sango cultured pearl" are recorded with no restriction on use as a name, while "Cortez cultured pearl", "Dobo pearls", "Fiji cultured pearl" and "Gulf cultured pearl" may appear only as an annotation, never as the product name (CIBJO Pearl Book 2024 §5.51 “Cortez cultured pearl”; GB/T 16552—2017 §5.1.2.3 c); GB/T 16552—2017 §5.1.1 c); CIBJO Pearl Book 2024 §5.62 “Dobo pearls”; CIBJO Pearl Book 2024 §5.69 “Fiji cultured pearl”; CIBJO Pearl Book 2024 §5.90 “Gulf cultured pearl”); one further name in a non-Latin script is listed in the name register below (1 with no restriction recorded on use as a name).
Standard and listing namesThe GB/T 16552—2017 formal name for Saltwater Cultured Pearl is given in Table A.3 as “Saltwater cultured pearl (seawater pearl)”, which may be shortened to “seawater pearl”; the suggested listing name is Saltwater Cultured Pearl (stating the type). Names in four languagesThe names are given in Simplified Chinese, Traditional Chinese, English (Saltwater Cultured Pearl) and Japanese; the Japanese name is the entry's own, and the Japanese GSJ wording for it has not yet been checked. Trade and mineralogical namesAmong market names, cultured pearl names such as Akoya, Tahitian and South Sea must match the facts and are matched only once the conditions are confirmed; market names such as Cortez, Dobo, Fiji and Gulf may only be added as a note, never as the main product name. Candidate search termsSango and Saltwater Pearl are only candidate search terms, and Saltwater Pearl rests on a GB/T 16552 revision consultation draft that is not in force and runs contrary to international pearl naming practice. Institution usageThe FTC source text has no wording for this name (checked), and GIA, CIBJO and Gem-A have not been checked; bodies without a recorded wording show the entry's own English name, Saltwater Cultured Pearl, which does not represent their position.
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 (4) | ||||
| Akoya/Tahitian/South Sea cultured pearlEnglish | market name | matched only once the condition is confirmed | no restriction recorded | editorial ruling (no clause cited) |
| Saltwater PearlEnglish | short form | search candidate only | no restriction recorded | GB/T 16552 revision draft for comment (2023, not in force) Table A.3; GB/T 16552—2017 5.1.2.3 b); CIBJO Pearl Book 2024 Annex C §8.1 “Saltwater Pearl”; Note: Draft standard for comment, not in force; the usage is the opposite of international pearl nomenclature. |
| Sango cultured pearlEnglish | market name | search candidate only | no restriction recorded | CIBJO Pearl Book 2024 §5.175 “Sango cultured pearl” |
| 海水珍珠Simplified Chinese | short form | matched automatically | no restriction recorded | GB/T 16552—2017 5.1.2.3 b); GB/T 16552—2017 Table A.3 “Saltwater Cultured Pearl”; GB/T 18781—2023 3.2.1 |
| annotation only, never as the product name (4) | ||||
| Cortez cultured pearlEnglish | market name | matched automatically | annotation only, never as the product name | CIBJO Pearl Book 2024 §5.51 “Cortez cultured pearl”; GB/T 16552—2017 5.1.2.3 c); GB/T 16552—2017 5.1.1 c) |
| Dobo pearlsEnglish | market name | matched automatically | annotation only, never as the product name | CIBJO Pearl Book 2024 §5.62 “Dobo pearls”; GB/T 16552—2017 5.1.2.3 c); GB/T 16552—2017 5.1.1 c) |
| Fiji cultured pearlEnglish | market name | matched automatically | annotation only, never as the product name | CIBJO Pearl Book 2024 §5.69 “Fiji cultured pearl”; GB/T 16552—2017 5.1.2.3 c); GB/T 16552—2017 5.1.1 c) |
| Gulf cultured pearlEnglish | market name | matched automatically | annotation only, never as the product name | CIBJO Pearl Book 2024 §5.90 “Gulf cultured pearl”; GB/T 16552—2017 5.1.2.3 c); GB/T 16552—2017 5.1.1 c) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- 海水養殖真珠 (not yet checked for this body — the entry's own Japanese name is shown)
- Chinese formal name
- 海水养殖珍珠 (GB/T 16552—2017 Table A.3, row “Saltwater Cultured Pearl”)
- Mineralogical name
- Cultured pearl formed in a marine mollusc
- Trade names and synonyms
- Akoya/Tahitian/South Sea cultured pearl (market name; conditional name) · Cortez cultured pearl (market name; annotation only, never as the product name) · Dobo pearls (market name; annotation only, never as the product name) · Fiji cultured pearl (market name; annotation only, never as the product name) · Gulf cultured pearl (market name; annotation only, never as the product name) · Sango cultured pearl (market name; conditional name) · Saltwater Pearl (short form; conditional name)
Four-language names
- 简体中文
- 海水养殖珍珠
- 繁體中文
- 海水養殖珍珠
- English
- Saltwater Cultured Pearl
- 日本語
- 海水養殖真珠
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural organic and biogenic materials
- Browsing family
- Pearl and molluscan shell materials
- Identity tier
- Organic or biogenic material
- Mineral chemical class
- Not applicable
- Construction or treatment status
- Cultured formation; treatments recorded separately
Treatments listed by standards
The treatment classification for Saltwater Cultured Pearl under GB/T 16552—2017 Annex B, Table B.1 is applied by this site from the Cultured Pearl (Pearl) row of Table B.1: bleaching is listed as optimization, dyeing as treatment and irradiation as treatment. Table B.1 lists the Cultured Pearl (Pearl) row; it has no separate treatment row for Saltwater Cultured Pearl.
GB/T 16552-2017, Annex B, Table B.1
Under the “Cultured Pearl (Pearl)” row of Table B.1: Bleaching Optimization; Dyeing Treatment; Irradiation Treatment. The full row, with the effect column, is on the Cultured Pearl 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.
What it is and how it's identified
The composition (chemistry) and density of Saltwater Cultured Pearl are registered for saltwater cultured pearls: the composition is relatively high in trace elements such as Sr, S, Na and Mg and relatively low in trace elements such as Mn; density is 2.72–2.78 g/cm³. The structure, registered for cultured pearls (the whole class), is an aggregate whose inorganic part is radially arranged, with aragonite orthorhombic and calcite trigonal, and whose organic part is amorphous. Registered for cultured pearls (the whole class), Mohs hardness is 2.5–4, and cleavage is usually not seen in the aggregate. Registered for cultured pearls (the whole class), the optic character is that of an aggregate, birefringence cannot be measured on the aggregate, and refractive index is 1.53–1.68; 1.53–1.68 is a spot-method reading, a typical value rather than an absolute limit, and the cited clause has further sub-grades, 1.53–1.68 being the overall value. Registered for cultured pearls (the whole class), the stability of untreated Saltwater Cultured Pearl is shown by its effervescence on contact with acid, and the lustre is pearly.
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 cultured pearl (the whole class), so they are not repeated on the Saltwater Cultured Pearl page; see the material facts on the Cultured Pearl entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Saltwater Cultured Pearl (how to read class-level values).
Definition
Saltwater Cultured Pearl: a cultured pearl produced by a saltwater mollusc (5.121).
CIBJO Pearl Book 2024
- Qualification
CIBJO trade definition from an institutional manual, not a national standard.
Source & check 2026-09-25
- Source
- CIBJO Blue Book — Pearl Book (Pearl Commission 2024-1) (CIBJO): §5.173, p.42 (locator checked 2026-09-25)
- Fact checked on
- 2026-09-25
Saltwater Cultured Pearl — composition (chemistry): relatively rich in trace elements such as Sr, S, Na and Mg, and relatively poor in trace elements such as Mn.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 Chemical composition · Saltwater pearl (locator checked 2026-09-28)
- Fact checked on
- 2026-09-26
Structure
Saltwater Cultured Pearl — structure (overall): inorganic part: aragonite (orthorhombic) and calcite (trigonal) in radiating aggregates; organic part: amorphous.
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Saltwater Cultured Pearl — Mohs hardness: 2.5–4
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
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — cleavage: generally not seen on an aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — stability: effervesces in acid
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Physical properties
Saltwater Cultured Pearl — density: 2.72–2.78 g/cm³
GB/T 16553—2017
- Does this standard apply
- applies to this entry
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 Density · Saltwater cultured pearl (locator checked 2026-09-28)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — feel (texture): feels gritty when two surfaces are rubbed together
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Saltwater Cultured Pearl — optic character: aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — refractive index: 1.53–1.68
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
- Qualification
The clause we cite gives this as a value read by the spot (distant-vision) method. It is a common value, not an absolute limit.
- General note
- the clause has finer ranges
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — birefringence: not measurable on an aggregate
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — pleochroism: not measurable on an aggregate
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Quality factors
Saltwater Cultured Pearl — quality factor (lustre): pearly
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- cultured pearl (the whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.3.2 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Saltwater Cultured Pearl — quality factor (shape and size): perfectly round (A1) ≤1.0%; round (A2) ≤5.0%; near-round (A3) ≤10.0%; short oval (B1) and long oval (B2) >10.0% (one merged cell in the source); high button (C1) and low button (C2): symmetrical, one or both sides nearly flat (one merged cell in the source; no percentage given); baroque (D): usually uneven, no obvious symmetry (no percentage given).
GB/T 18781—2023
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- Measurement condition
- GB/T 18781—2023 §6.2 and §6.3: maximum and minimum dimensions measured with a gauge graduated to 0.02 mm or finer; diameter difference X=(dmax−dmin)/d×100, one decimal place
- Qualification
In the saltwater column of Table 1 the two oval grades share one merged cell (>10.0%), and the two button grades get only a shape description (symmetrical, one or both sides nearly flat) with no percentage; the standard does not split them further and neither does this page. Size is not graded.
Source & check 2026-09-26
- Source
- GB/T 18781—2023 Cultured pearl grading (GB/T): §4.3 Table 1 (saltwater column), §6.3 (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): 1.605 / 2.75; Closest values: 1Larimar 1.62 / 2.82, 2Natural Conch Pearl / Natural Melo Pearl 1.595 / 2.84, 3Aquamarine 1.58 / 2.79, 4Turquoise 1.63 / 2.65, 5Prehnite 1.625 / 2.88
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
Pearl-producing molluscs (CIBJO Annex D)
Pearl-producing molluscs (CIBJO Annex D): §9.1 Abalone · §9.3 Akoya pearl oyster · §9.5 Aliger gigas · §9.9 Australian akoya pearl oyster · §9.10 Australian south-sea pearl oyster · §9.11 Black-lipped pearl oyster · §9.26 Gold-lipped pearl oyster · §9.33 La Paz pearl oyster · §9.54 Pinctada fucata · §9.56 Pinctada maculata · §9.58 Pinctada margaritifera cumingii · §9.59 Pinctada margaritifera typica · §9.60 Pinctada maxima · §9.61 Pinctada mazatlanica · §9.63 Pinctada maculata · §9.69 Pteria sterna · §9.78 Silver-lipped pearl oyster
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: Pearl Description.
- CIBJO – The World Jewellery Confederation. The Pearl Book (Blue Book), 2024.
- eCFR (United States). 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 Pearl on this site: 17 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Saltwater Cultured Pearl) is marked.
- Pearl
Sub-entries (16)
- Abalone Pearl
- Akoya Cultured Pearl
- Baroque Cultured Pearl
- Blister Pearl
- Circled Cultured Pearl
- Cultured Pearl
- Freshwater Cultured Pearl
- Freshwater Natural Pearl
- Keshi Cultured Pearl
- Natural Conch Pearl / Natural Melo Pearl
- Natural Pearl
- Saltwater Cultured Pearl
- Saltwater Natural Pearl
- South Sea Cultured Pearl
- Tahitian Cultured Pearl
- White South Sea Cultured Pearl
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Pearl and molluscan shell materials | Live |
| Treatments recorded for this material | Bleached (via parent material), Dyed (via parent material), Irradiated (via parent material) | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Saltwater Cultured Pearl 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. The entry exists so that buyers and sellers can check naming, disclosure and material facts item by item.