On this page
UnderstandWhat it is, what people ask, how far this page goes
Natural inorganic gem materials · Natural glass · Natural identity; treatment status unknown
Snowflake Obsidian
Obsidian containing cristobalite spherulites; the white “snowflakes” are a pattern of spherulites, not real snowflakes. 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 Snowflake Obsidian 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 Snowflake ObsidianHow far lab testing can go and whether a synthetic exists
- Hardness and refractive index of Snowflake ObsidianEach value with its source and check date
- Snowflake Obsidian in English, Chinese and Japanese; national standard namesNames in four languages, the GB/T standard name and the suggested listing name; and: Which of GIA, FTC, CIBJO and Gem-A have a name for it on record, and do those agree?
- Listing and disclosing Snowflake ObsidianThe listing name to use; what must be disclosed before sale
- Standard clauses that define Snowflake ObsidianWhich 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
Snowflake obsidian is obsidian bearing cristobalite spherulite 'snowflakes'; its parent material is obsidian, a natural volcanic glass formed when silica-rich magma cools too fast to crystallize, occurring only in volcanic regions. The sources in this record do not describe the mechanism of the 'snowflake' pattern (cristobalite spherulites / devitrification), so that pattern mechanism is flagged as an evidence gap; only the parent obsidian's formation is presented.
Scope: Covers an overview of the formation of snowflake obsidian; formation content follows that of the parent material obsidian, and evidence for the formation mechanism of the cristobalite spherulite "snowflake" spots is lacking in the cited authoritative sources.
Sources NPS Hopewell Culture · NPS Obsidian Cliff · CIBJO Gemstone Book 2022 +1
Where it forms
Volcanic regions where silica-rich (rhyolitic/dacitic) magma cools rapidly.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
The parent obsidian is a glassy natural glass, black but also brown, tan, or green.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
How it forms, step by step
Silica-rich magma rises to the surface and cools rapidly.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
Cooling is too fast for atoms to arrange as crystals, producing amorphous volcanic glass.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
During solidification, aligned micro-inclusions/thin layers are preserved inside, giving the sheen/iridescent appearance.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
Link to appearance
An appearance-based name ('sheen') describes an optical effect and cannot alone establish identity, naturalness, treatment, or origin.
Sources CIBJO Gemstone Book 2022 · G&G Summer 2025
Timescale
The sources in this record give no absolute age or growth duration for this variety.
Sources NPS Hopewell Culture · NPS Obsidian Cliff
Related base materials
- obsidian: Obsidian is the parent material of this name; this name is an occurrence/optical variety name, not a separate material
Supporting findings
Obsidian is a natural volcanic glass (a glassy igneous rock) formed when silica-rich magma cools so rapidly that it does not crystallize, so it occurs only where there is volcanic activity.
Evidence grade AScope: Applies to the natural origin of obsidian (the parent material); it states rapid cooling, not a specific eruption age.
Sources NPS Obsidian Cliff · NPS Hopewell Culture
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
North America
- Black Rock Desert, Millard County, Utah, United States
Sources Mindat: Snowflake Obsidian
- Glass Buttes, Lake County, Oregon, United States
Sources Mindat: Snowflake Obsidian
South America
- Salar del Hombre Muerto, Catamarca, Argentina
Sources Mindat: Snowflake Obsidian
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
The name refers to a variety of obsidian (parent material obsidian) whose appearance arises from reflection off internal aligned inclusions.
Evidence grade AScope: Describes the optical mechanism (reflection from aligned inclusions, sometimes aventurescence); does not claim it is an independent material.
Other research findings
In CIBJO gemmological nomenclature, obsidian is listed as a 'natural glass', an amorphous natural gem material rather than a mineral species.
Evidence grade AScope: Defines the material class of obsidian (natural glass); not a specific variety.
Sources CIBJO Gemstone Book 2022
Studies of these aligned-inclusion/thin-layer sheens in obsidian are still limited, and sheen obsidians from different localities differ markedly, so multiple mechanisms may be involved.
Evidence grade AScope: Acknowledges limited evidence; does not claim one mechanism explains all golden/silver sheen obsidian.
Limits of this research
- Research status: Formation, occurrence or other material-specific findings found in authoritative sources
- The sources do not describe the mechanism of the cristobalite-spherulite 'snowflake' pattern; that pattern's origin is an evidence gap.
- Obsidian is a natural glass, not a mineral species; the variety name describes appearance only and is not a determinable material.
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
- Snowflake Obsidian
GB/T 16552—2017 5.1.1 c) · CIBJO Gemmological Laboratories Book 2024 §7.2.1.219 “Snowflake obsidian”
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
"Snowflake Obsidian" is a market name rather than a mineral species name; before using it, verify: Industry-wide term that does not denote a single species.
What this means for you
Before buying, check the recommended listing name "Snowflake Obsidian" 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
- Industry-wide term that does not denote a single species.
- Suggested listing name
- Snowflake Obsidian
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Snowflake Obsidian, the name register records "Snowflake obsidian", for which no restriction on use as a name is recorded.
Standard and listing namesThe GB/T 16552—2017 Table A.2 naming counterpart for Snowflake Obsidian is natural glass, and the standard does not list the name Snowflake Obsidian; the mineralogical name is obsidian containing cristobalite spherulites; the trade name or synonym is Snowflake obsidian; and the suggested listing name is Snowflake Obsidian. Names in four languagesNames are registered in four languages: Simplified Chinese, Traditional Chinese, English (Snowflake Obsidian) and Japanese. Institution usageOn authority wording, the CIBJO Gemmological Laboratories Book 2024 records Snowflake Obsidian; the FTC text on file has no wording for Snowflake Obsidian (checked); GIA and Gem-A are unchecked, and bodies without a recorded wording show the entry's own English name, which does not represent their position. Japanese namesThe Japanese name shown is the entry's own; the wording used by the GSJ (Japan) for it is not yet verified by this site.
Name register
Every name recorded for this entry, with how it is classified, whether it may be matched to this entry automatically, whether it may be used as a product name, and the clause it rests on.
This table scrolls sideways on narrow screens.
| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (1) | ||||
| Snowflake obsidianEnglish | market name | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
How each authority words this name: see Names › Authority wording.
- GSJ (Japan) formal name
- スノーフレークオブシディアン (not yet checked for this body — the entry's own Japanese name is shown)
- GB/T naming counterpart (this name is not in the standard)
- 天然玻璃 (GB/T 16552—2017 Table A.2)
- Mineralogical name
- Obsidian with cristobalite spherulites
Four-language names
- 简体中文
- 雪花黑曜石
- 繁體中文
- 雪花黑曜石
- English
- Snowflake Obsidian
- 日本語
- スノーフレークオブシディアン
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Natural glass
- Identity tier
- Natural glass
- Mineral chemical class
- Not applicable
- Construction or treatment status
- Natural identity; treatment status unknown
What it is and how it's identified
For the registered material facts of Snowflake Obsidian, structure, Mohs hardness, cleavage, optic character, refractive index, birefringence, lustre and similar items take the values for natural glass (whole class). For natural glass (whole class): the structure is amorphous; there is no cleavage; Mohs hardness is 5–6 (a range for the whole class, since the cited clause covers natural glass, including both tektites and volcanic glass); the optic character is isotropic, commonly with anomalous extinction; refractive index is 1.48–1.51 (derived from the cited clause's 1.490 with a tolerance of +0.020, −0.010); there is no birefringence; and the untreated quality factor (lustre) is vitreous. Chemical composition, luminescence, UV-visible spectrum, infrared spectrum and magnification are written for natural glass (whole class); see the material facts on the Natural Glass entry.
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 natural glass (whole class), so they are not repeated on the Snowflake Obsidian page; see the material facts on the Natural Glass (material) entry.
Items below that name the class they cover give the cited clause’s value for that whole class, not a measurement of Snowflake Obsidian (how to read class-level values).
Structure
Snowflake Obsidian — structure (overall): amorphous (not crystalline)
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Durability
Snowflake Obsidian — Mohs hardness: 5–6
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
- natural glass (whole class)
- Qualification
This is the range for the whole class, not a measured value for this variety. The clause covers all natural glass (tektite and volcanic glass).
Source & check 2026-09-20
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-20)
- Fact checked on
- 2026-09-20
Snowflake Obsidian — cleavage: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Optical
Snowflake Obsidian — optic character: isotropic, usually with anomalous extinction
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Snowflake Obsidian — refractive index: 1.48–1.51
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
- Qualification
The clause we cite gives 1.490, with a stated tolerance of +0.020 / -0.010. The range shown here is worked out from that.
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Snowflake Obsidian — birefringence: none
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-21
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-21)
- Fact checked on
- 2026-09-21
Snowflake Obsidian — pleochroism: none
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Snowflake Obsidian — optical effect (chatoyancy): seen; rare
GB/T 16553—2017
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (locator checked 2026-09-26)
- Fact checked on
- 2026-09-26
Snowflake Obsidian — body colour: white patches in a black or dark grey background.
CIBJO Gemmological Laboratories Book 2024
- Treatment state
- untreated
- Qualification
In chapter 7 of the CIBJO Gemmological Laboratories Book, the colour descriptions of Howlite, Opal, Onyx and other entries also name white or a whitish colour.
- General note
- colour alone is not identity
Source & check 2026-09-26
- Source
- Fact checked on
- 2026-09-26
- CIBJO definitions
- chatoyancy
Quality factors
Snowflake Obsidian — quality factor (lustre): vitreous
GB/T 16553—2017
- Treatment state
- untreated
- Does this standard apply
- applies to this entry
- What this covers
- natural glass (whole class)
Source & check 2026-09-26
- Source
- GB/T 16553—2017 Gems — Testing (GB/T): §5.2.29 (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.
Testing and market
On synthetics: there is no synthetic Snowflake Obsidian on the market. On identification, the CIBJO laboratory protocol places Snowflake Obsidian under obsidian; for identification see identification on the Obsidian entry, and the list of required methods is on the laboratory testing page.
The CIBJO laboratory protocol covers Snowflake Obsidian under “Obsidian” (§6.1.55): see identification on the Obsidian entry; the required tests are listed on the CIBJO laboratory protocol table for Obsidian.
How far testing can go
Snowflake Obsidian — synthetic counterpart on the market: No synthetic counterpart of this material is commercially available
CIBJO Gemstone Book 2022
- Treatment state
- any treatment state
Source & check 2026-09-22
- Source
- Fact checked on
- 2026-09-22
Each row's “Source & check” expands to the full source; the date beside it is the fact check date.
Clause-level definitions
Snowflake Obsidian has a direct clause-level definition in the CIBJO Gemmological Laboratories Book 2024, recorded under the term Snowflake obsidian; the definition describes Snowflake Obsidian as showing white patches on a black or dark grey ground. This site's cross-check result is defined directly by CIBJO, with no English name of the same name found directly in the GB/T annex of this edition.
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| Term | Clause | Definition | Cross-check |
|---|---|---|---|
| Snowflake obsidian | 7.2.1.219 | Snowflake obsidian shows white patches in a black or dark grey background | 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
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 Natural Glass (material) on this site: 7 entries listed by this site's parent-entry links; synthetic, treated and similar entries carry their recorded state after the name; this page (Snowflake Obsidian) is marked.
- Natural Glass (material)
Sub-entries (6)
This table scrolls sideways on narrow screens.
| Page | Content | Status |
|---|---|---|
| Browsing family | Natural glass | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The material facts in the Snowflake Obsidian 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.