Is jade a mineral?
Jade is two rocks, not one mineral: jadeite (hardness 6 to 7) and nephrite, a tremolite-actinolite amphibole. Quartz, calcite, prehnite, malachite pose as it.
Jade is not a single mineral. It is a name for two tough rocks: jadeite jade, made of the pyroxene jadeite, an IMA species with hardness 6 to 7; and nephrite, a fibrous aggregate of tremolite–actinolite amphibole. GIA also admits some green omphacite. Neither jade nor nephrite has a row on the IMA list, by script.
In short
- The criteria first. Three questions decide which word is right for a piece: is the name for a mineral or a rock; which mineral dominates the rock; and is the name a trade name for something else. Jadeite answers the first as a mineral; jade and nephrite answer it as rocks.
- Jade is a rock. GIA writes that jadeite and nephrite are actually metamorphic rocks of tiny interlocking mineral crystals, and that modern gemmologists use jade as a generic term for nephrite, jadeite and, under certain conditions, green omphacite. The IMA-CNMNC Master List has a row for jadeite and for omphacite, and none for jade.
- Nephrite is not a species. The International Gem Society places nephrite in the tremolite-actinolite series. The actinolite sheet records tough fibrous aggregates as “nephrite jade”. The IMA list has rows for actinolite and tremolite and none for nephrite. Hobbs wrote in 1982 that the IMA had discredited nephrite as a mineralogical variety.
- The 30-name count. Hobbs’s Gems & Gemology table of misleading terms lists 30 names for jade simulants under 13 headings, from “Mexican jade” (dyed calcite) to “Transvaal jade” (grossular). None of the 30 is jadeite or nephrite. One, “Silver Peak jadeite”, uses the species name itself for malachite.
- Who each word is wrong for. Jadeite is wrong for nephrite; nephrite is wrong for jadeite; “jade” alone is right for both and says nothing about which. A place name before jade is a warning, not a locality.
| Label on the piece | What it names | IMA row? | Hardness | Specific gravity | Wrong for |
|---|---|---|---|---|---|
| Jadeite | A mineral species, NaAlSi2O6, pyroxene | Yes | 6 to 7 (sheet); 6.5 to 7 (GIA) | 3.24 to 3.43 (sheet); 3.34 (GIA) | Nephrite; a piece mostly omphacite |
| Jadeite jade | A rock made mostly of jadeite (GIA) | No row for jade | 6.5 to 7 (GIA) | 3.34 (GIA) | Mixed pyroxene pieces only a laboratory can name |
| Nephrite | A rock of interwoven tremolite–actinolite fibres (IGS; Hobbs) | No; actinolite and tremolite have rows | 6.0 to 6.5 (GIA) | 2.95 (GIA) | Jadeite jade |
| Omphacite jade | Green omphacite, jade under certain conditions (GIA) | Yes, omphacite | 5 to 6 (sheet) | 3.16 to 3.43 (sheet) | Anyone without Raman testing: GIA says it needs advanced methods |
| Fei cui | Traditional Chinese term for jadeite jade; now also used for kosmochlor and omphacite (GIA) | No | A buyer expecting one species | ||
| Imperial jade | The finest jadeite, almost transparent, vibrant emerald-green (GIA) | No | As jadeite | As jadeite | Nephrite, which GIA’s definition excludes |
| “Korean jade”, “Indian jade”, “Transvaal jade”, “American jade”, “Mexican jade” | Serpentine; aventurine quartz; green hydrogrossular garnet; green idocrase; tinted green marble (IGS) | Antigorite, quartz, grossular, vesuvianite and calcite have rows; the trade words do not | 2.5 to 3.5 (antigorite) to 7 (quartz) | 2.65 (quartz, antigorite) to 3.594 (grossular) | Everyone: none is jade |
| Any of Hobbs’s 30 misleading terms | 13 simulant headings, calcite to grossularite | 10 of the 13 headings name a mineral with a row | 1 (talc) to 7 | 0 of 30 are jadeite or nephrite |
Is jade a mineral or a rock?
Jade is a rock name, not a mineral name. GIA’s jade description says that jadeite and nephrite, the materials long accepted as jade, are actually metamorphic rocks made up of tiny interlocking mineral crystals which make the gems exceptionally tough. A mineral is a species with a defined composition and structure, and the IMA list is the register of them; a rock is an aggregate. The general test is worked on is quartz a mineral and not repeated here; the same mineral-or-rock problem is on is lapis lazuli a mineral or rock.
What the IMA list shows. A script over the September 2026 list finds rows for jadeite (NaAlSi2O6, status A), omphacite, kosmochlor, aegirine, actinolite and tremolite. It finds none for jade, nephrite, imperial, fei cui, chloromelanite or jadeitite. Jadeite and omphacite are minerals that jade can be made of. Jade is the stone made of them.
Why the toughness matters. Hobbs, in Gems & Gemology in 1982, defines the texture as part of the material: for nephrite, interlocking fibres; if the fibres are merely parallel, the material lacks the toughness and is not nephrite. A single crystal of jadeite is a mineral specimen; a carving in jade is a rock. The broader distinction is on crystal vs mineral.
Jadeite or nephrite: which jade is it?
Jadeite is a pyroxene. Its Handbook sheet gives hardness 6 to 7, density 3.24 to 3.43 and indices from 1.640 to 1.692; GIA gives 1.666 to 1.680 and specific gravity 3.34. The species page is jadeite.
Nephrite is an amphibole rock. The International Gem Society says it belongs to the tremolite-actinolite series: closer to tremolite, more magnesium and lighter colours, such as the creamy white called mutton fat; closer to actinolite, more iron and darker greens. GIA gives it 1.606 to 1.632 and specific gravity 2.95. The actinolite sheet’s tenacity line reads tough in fibrous aggregates (“nephrite jade”). Whether a fibrous amphibole is regulated as asbestos is a different question, set out on is actinolite asbestos; nothing here is safety advice.
The dates. Hobbs records that Damour placed nephrite with tremolite and actinolite in 1846 and showed in 1863 that jadeite is a separate species. The IMA row for jadeite cites the Comptes Rendus of 1863. Which of the two a given piece is, and how to tell it from glass or serpentine, is on how to tell if jade is real.
The 30-name count: jades that are not jade
The 30-name count: of the 30 misleading terms in Hobbs’s 1982 table, none names jadeite or nephrite. Hobbs, “The Jade Enigma”, Gems & Gemology, Spring 1982 lists, by simulant: dyed calcite, “Mexican jade”; chalcedony, “Queensland jade”, “Swiss jade”, “Jasper jade”, “Oregon jade”; partly devitrified glass, “Metajade”; idocrase, “Vesuvianite jade”, “American jade”, “California jade”; malachite, “Silver Peak jadeite”; amazonite, “Amazon jade”, “Colorado jade”; pectolite, “Alaska jade”, “Pectolite jade”; prehnite, “Japanese jade”; pseudophite, “Styrian jade”; aventurine quartz, “Regal jade”, “Indian jade”, “Imperial yu”; antigorite serpentine, “Korean jade”, and its bowenite variety, “Soochow jade”, “New jade”; talc, “Fukien jade”, “Honan jade”, “Manchurian jade”, “Shanghai jade”; grossularite, “Transvaal jade”, “South African jade”, “Garnet jade”, “White jade”.
Counted by script from that transcription, made from the rendered page: 30 terms under 13 headings; 29 contain the word jade, the other being “Imperial yu”; 10 of the 13 headings name a mineral with an IMA row (calcite, vesuvianite for idocrase, malachite, microcline, pectolite, prehnite, quartz, antigorite, talc and grossular), and 3 do not (chalcedony, glass, pseudophite). The International Gem Society’s shorter list gives 5 jade names, and each matches a Hobbs entry: Korean jade, serpentine; Indian jade, aventurine; Transvaal jade, green hydrogrossular garnet; American jade, green idocrase; Mexican jade, tinted green marble.
A documented conflict. Hobbs gives “Alaska jade” as a name for pectolite, and GIA’s buyer’s guide lists Alaska jade among terms that generally refer to other minerals. Yet the actinolite sheet names nephrite around Jade Mountain near the Kobuk River, Alaska, and the International Gem Society describes Alaskan nephrite. An “Alaska jade” label is therefore ambiguous in both directions; only a test settles it.
Who each word is wrong for
“Jadeite” is wrong for nephrite, and for a green piece that is mostly omphacite. GIA says some green omphacite has the same gemmological properties as jadeite and is identified by Raman spectra, which needs advanced testing. A home test cannot apply this label to a mixed pyroxene.
“Nephrite” is wrong for jadeite, and for parallel-fibred amphibole that lacks the interlocking texture, on Hobbs’s definition. “Jade” alone is right for both and tells you neither the mineral nor the density to expect; on a specimen label, name the mineral where it is known.
A place name in front of jade is the case to distrust. Of the 30 Hobbs terms, 20 are a place name followed by jade or jadeite, from Mexican to Shanghai (we do not count “Amazon jade” as a place), and every one names a simulant. The other identification pages are at the collecting guides. Nothing on this site is offered for sale; the wanted list is the only commercial route.