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Natural inorganic gem materials · Rock / mineral aggregate · Natural identity; treatment status unknown
Lava Stone
Also known aslava rock
A porous basaltic volcanic scoria rock, not a mineral species. GB/T does not list this name, and it is not the same material as Obsidian. Also known as lava rock. 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.
Questions people ask about Lava Stone
Every sentence below is followed by the registered fact it rests on; answers add no new facts and promise no outcome.
Q1What is lava stone made of?
Lava stone is a volcanic rock full of gas holes, such as basaltic scoria: a rock made of several minerals, with no single chemical formula, not a mineral species.USGS VolcanoesBasalt is a dark grey to black volcanic rock with about 45 to 53 percent silica, rich in iron and magnesium, and scoria is usually basaltic too.USGS Volcano Glossary · NPS Igneous Rocks
Q2Why is lava stone full of holes?
The holes form as gases dissolved in the magma come out of solution and expand while the magma rises and the pressure drops.USGS VolcanoesIn scoria these gas bubbles, called vesicles, make up most of the rock's volume.USGS Volcano Glossary · NPS PyroclastsThe magma then solidifies quickly near the surface, which keeps the rock fine-grained or glassy.USGS Volcanoes
Q3How is lava stone different from pumice and obsidian?
All three are volcanic, but pumice is pale with very thin glass walls between its bubbles and is often light enough to float, while scoria is darker and denser than pumice.USGS Volcano Glossary · NPS Pyroclasts +1Obsidian is dense volcanic glass, usually black, formed where lava cooled too fast for crystals to grow.USGS Volcano Glossary · NPS Pyroclasts +1
What this page can answer
This page covers
- How Lava Stone forms and what gives its colourFormation setting, process and timescale, each finding graded and sourced
- Lava Stone 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 Lava StoneThe 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
Volcanic stone is a vesicular volcanic rock (e.g. basaltic scoria). It is a polymineral aggregate (a rock) with no single chemical formula, so its identity is that of a rock / commercial material name rather than a mineral species. It forms when magma erupts at the surface and solidifies rapidly: lava cooled near or on the Earth's surface is finely crystalline or glassy (matrix of quenched or super-cooled magma), so volcanic rocks typically contain a small percentage of crystals or fragments. Its characteristic porous texture arises from the exsolution and expansion of dissolved gases as the magma decompresses on ascent—violent separation of gas from lava can produce rock froth (pumice), and the cavities are preserved in the solidified rock.
Scope: Applies to explaining the identity of lava stone as a volcanic rock with vesicular structure and its rock-forming / vesicle origin; not applicable to determining the specific lithology, mineral composition, locality or value from the name.
Sources USGS Volcanoes
Where it forms
Volcanic vent eruption: a volcano is built by the accumulation of its own eruptive products (lava, bombs, tephra).
Sources USGS Volcanoes
Near-surface rapid-cooling setting: lava cools rapidly to form finely crystalline or glassy volcanic rock.
Sources USGS Volcanoes
How it forms, step by step
Magma generated in the mantle or crust rises and decompresses.
Sources USGS Volcanoes
Dissolved gases exsolve and expand (violent separation can form rock froth/pumice).
Sources USGS Volcanoes
Lava solidifies rapidly near or at the surface, preserving the cavities and forming vesicular volcanic rock.
Sources USGS Volcanoes
Link to appearance
It appears porous and rough, but appearance cannot substitute for identification of the specific rock type and mineral composition.
Sources USGS Volcanoes
Timescale
The cited sources give no absolute age or growth duration for volcanic stone.
Sources USGS Volcanoes
Related base materials
- Basalt (volcanic rock): The class of volcanic rock corresponding to lava stone (a rock, not a mineral species)
Supporting findings
Magma that erupts and solidifies rapidly forms volcanic rock; rapid cooling near the surface makes the rock finely crystalline or glassy.
Evidence grade AScope: Describes the lithification mechanism of volcanic rocks (including volcanic stone); not a locality-specific fact.
Sources USGS Volcanoes
A volcano is built up from the material it emits — lava, bombs and tephra — and is emplaced in a vent or fissure eruption setting.
Evidence grade AScope: Describes the setting of volcanic rocks; not tied to any specific locality of a particular volcanic stone.
Sources USGS Volcanoes
Scoria, the usual material of lava stone, is volcanic ejecta made of magma frothed up by escaping gases. Its holes (vesicles) began as gas bubbles that grew as dissolved gases came out of the magma during eruption, and in scoria they make up most of the rock's volume. USGS describes scoria as a textural variant of pumice that is usually basaltic or andesitic.
Evidence grade AScope: General geology of scoria; it does not establish what any particular commercial "lava stone" bead is made of.
Sources USGS Volcano Glossary · NPS Pyroclasts
Recorded localities
Authoritative sources list the localities below; the list is not exhaustive.
Seas and coasts
- Worldwide (volcanic terrains)Volcanic rocks are globally widespread; the source gives no specific locality
Sources USGS General Interest Publication
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.
Other research findings
Volcanic stone is a vesicular volcanic rock (e.g. basaltic scoria); it is a polymineral aggregate (a rock) with no single chemical formula and is not a mineral species.
Evidence grade BScope: A rock/aggregate identity judgement; the specific rock type and mineral composition require identification.
Sources USGS Volcanoes
The porous texture of volcanic stone arises from the exsolution and expansion of dissolved gases as magma decompresses on ascent; violent separation can form rock froth (pumice).
Evidence grade AScope: Explains the vesicular texture; a generic volcanic-rock mechanism, not exclusive to the name 'volcanic stone'.
Sources USGS Volcanoes
Basalt is dark (grey to black) volcanic rock containing about 45 to 53 percent silica and rich in iron and magnesium. It is the most common volcanic rock on Earth and is often full of gas holes; scoria and cinders are usually basaltic in composition too.
Evidence grade AScope: Textbook-level definitions from US federal geoscience agencies; the silica ranges quoted by different pages differ slightly (USGS 45–53%, NPS 45–52%).
Sources USGS Volcano Glossary · NPS Igneous Rocks
Scoria, pumice and obsidian are all volcanic but differ in texture. Pumice is light-coloured, usually rhyolitic, with small bubbles separated by very thin glass walls; it is often light enough to float on water. Scoria is darker, typically less bubbly and denser than pumice. Obsidian is dense volcanic glass, usually black, formed where lava cooled too fast for crystals to grow.
Evidence grade AScope: The sources say pumice can float and scoria is denser than pumice; none of them states as a rule whether scoria sinks or floats, so the site should not claim either.
Sources USGS Volcano Glossary · NPS Pyroclasts · USGS Volcanoes
Limits of this research
- Research status: No authoritative source specific to this material was found; findings come from the parent material or are marked as gaps
- Volcanic stone is a rock (polymineral aggregate), not a mineral species; no specific rock type, mineral composition or locality is confirmed.
- The cited source is a USGS general-volcanology publication, not material dedicated to the 'volcanic stone' trade name.
- Not a judgement of authenticity, grade or value.
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
- Lava stone (vesicular volcanic rock)
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
"Lava Stone" is a market name rather than a mineral species name; before using it, verify: Laboratory identification required before the name is used. Industry-wide term that does not denote a single species.
What this means for you
Before buying, check the recommended listing name "Lava stone (vesicular volcanic rock)" 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.
- Industry-wide term that does not denote a single species.
- Suggested listing name
- Lava stone (vesicular volcanic rock)
VerifyNames, standards, technical facts, clauses and sources
Names
Besides Lava Stone, the name register records "lava rock", for which no restriction on use as a name is recorded; 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 namesLava Stone is not listed in the national standard GB/T 16552—2017 Annex A and can be named directly, as Lava Stone; the suggested listing name is Lava Stone (porous volcanic rock). Trade and mineralogical namesMarket names include a Chinese name meaning “molten rock stone” and lava rock. The mineralogical name can be paraphrased as porous volcanic rock (basaltic scoria), a multi-mineral aggregate with no single chemical formula. Names in four languagesNames are registered in four languages: Simplified and Traditional Chinese (written identically), English (Lava Stone) and Japanese; for the GSJ (Japan) formal name, the wording used by the GSJ is not yet verified by this site, and the entry's own Japanese name is currently shown. Institution usageOn authority wording, the FTC and CIBJO texts on file have no wording for the name Lava Stone (checked); GIA and Gem-A are unchecked; bodies without a recorded wording for the name show the entry's own English name, Lava Stone, 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.
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| Name | Type | Matching | Use as a name | Basis |
|---|---|---|---|---|
| no restriction recorded (2) | ||||
| lava rockEnglish | market name | matched automatically | no restriction recorded | editorial ruling (no clause cited) |
| 熔岩石Simplified Chinese | 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
- ラバストーン／溶岩石 (not yet checked for this body — the entry's own Japanese name is shown)
- Mineral / material name (not in GB/T 16552 Annex A; usable directly)
- 火山石 (GB/T 16552—2017 §5.1.1 b))
- Mineralogical name
- Vesicular volcanic rock (basaltic scoria); a polymineral aggregate with no single chemical formula
- Trade names and synonyms
- lava rock (market name)
Four-language names
- 简体中文
- 火山石
- 繁體中文
- 火山石
- English
- Lava Stone
- 日本語
- ラバストーン／溶岩石
See also: Misleading and prohibited trade names · Supplementary name index
Classification
- Origin
- Natural materials
- Material domain
- Natural inorganic gem materials
- Browsing family
- Rocks and polymineral aggregates
- Identity tier
- Rock / mineral aggregate
- Mineral chemical class
- Mixed / composition-dependent
- Construction or treatment status
- Natural identity; treatment status unknown
What it is and how it's identified
There are no citable authoritative material facts for Lava Stone: the GB/T 16552, GB/T 16553, GB/T 34098 and GB/T 18781 standards and the material of CIBJO, GIA, AGTA, LMHC and other bodies that were checked do not cover it, and the lava mentioned in the CIBJO laboratory book refers to the origin of obsidian, which is not the same thing as lava stone beads. Lava Stone is a porous rock whose composition varies with locality and batch, so values such as hardness and density can only come from testing the actual piece. Geological sources such as the US Geological Survey volcano glossary only explain rock names such as scoria and vesicular basalt and do not say what beads sold as lava stone are; the specific claims all come from sellers' pages and do not agree, some saying basalt and others saying white and other colours are actually pumice, so they cannot serve as sources.
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”.
No citable material facts in the authoritative sources checked. None of the national standards consulted (GB/T 16552, 16553, 34098 and 18781), nor the CIBJO, GIA, AGTA or LMHC documents, covers lava stone. The CIBJO laboratory manual mentions lava only when describing how obsidian forms, not lava-stone beads. Lava stone is a porous rock whose make-up varies from source to source, so figures such as hardness or density have to come from testing the actual piece. Geological references such as the US Geological Survey's volcano glossary define rock names like scoria and vesicular basalt without saying what beads sold as lava stone are; the specific claims online come from sellers and disagree with one another (basalt in some, pumice for the white and coloured beads in others), so they cannot serve as sources.
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.
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| Page | Content | Status |
|---|---|---|
| Browsing family | Rocks and polymineral aggregates | Live |
| Related articles | To be added (placeholder) | Planned |
Who maintains this page
The names, standards basis and disclosure requirements in the Lava Stone entry are maintained by the LumaLark wiki and matched one by one to the standard clauses or institutional sources they cite. The entry exists so that buyers and sellers can check naming, disclosure and material facts item by item.