Honan jade — also written Henan jade, reflecting the modern Pinyin romanisation of the province — is a trade name applied to serpentine-group rock material sourced principally from Henan Province in central China and sold, historically and in some markets still today, as a form of jade. It is not true jade in any gemmological sense: neither jadeite (NaAlSi₂O₆, Mohs hardness 6.5–7) nor nephrite (a fibrous actinolite-tremolite amphibole, Mohs 6–6.5) but rather a metamorphic rock composed predominantly of serpentine minerals — chiefly antigorite and lizardite — with a Mohs hardness of only 2.5 to 4. The distinction matters enormously in commerce, as genuine jadeite and nephrite command prices orders of magnitude higher than serpentine, and the misapplication of the word "jade" to serpentine has been a persistent source of consumer confusion across several centuries of trade.

Mineralogy and Physical Properties

Serpentine is not a single mineral species but a group of phyllosilicate minerals sharing the general formula Mg₃Si₂O₅(OH)₄, in which iron, nickel, manganese, or chromium may substitute for magnesium to varying degrees. The green colouration characteristic of Honan jade arises primarily from iron and, in more vivid specimens, from traces of chromium. The material is typically translucent to semi-translucent, with a waxy to resinous lustre on polished surfaces. Specific gravity ranges from approximately 2.44 to 2.62, considerably lower than jadeite (3.25–3.36) or nephrite (2.90–3.03). The refractive index, measured by refractometer, falls in the range of approximately 1.49–1.57 — again clearly distinct from both jade species. Hardness is the most immediately diagnostic property in the field: a steel penknife blade (Mohs approximately 5.5) will scratch serpentine with ease, whereas jadeite and nephrite resist such treatment.

The rock texture of Honan jade is typically massive and fine-grained, lending itself well to carving. Colour ranges from pale yellowish-green and apple green through deeper olive tones; some material is nearly colourless or pale grey. Mottling, veining, and colour zoning are common. Translucency can be attractive in thin sections, and the material takes a reasonable polish, which historically made it a practical and affordable carving stone.

Geographic and Historical Context

Henan Province occupies the middle reaches of the Yellow River basin and has been a centre of Chinese civilisation since the Neolithic period. Serpentine deposits in the region have been exploited for decorative stonework for many centuries, and carved objects in this material appear in Chinese art markets and collections under a variety of regional names. The English trade name "Honan jade" reflects the older Wade-Giles romanisation of the province name (Honan = Henan in Pinyin) and is therefore encountered primarily in older Western auction catalogues, dealer inventories, and gemmological literature predating the widespread adoption of Pinyin in the late twentieth century.

The use of serpentine as a jade substitute or jade-adjacent carving material is by no means unique to Henan. Bowenite, a compact, translucent variety of antigorite with hardness approaching 5–5.5, has been used in New Zealand, Afghanistan, and China under various local names. Korean "jade" and certain Taiwanese green stones have similarly been identified as serpentine on gemmological testing. What distinguishes Honan jade as a trade category is its specific geographic attribution and its long presence in the Chinese domestic and export carving trade.

Gemmological Identification

Distinguishing Honan jade (serpentine) from true jade is straightforward with standard gemmological instruments and requires no advanced analytical equipment in most cases.

• Hardness: Serpentine is scratched by a steel blade; jadeite and nephrite are not. This single test, applied to an inconspicuous area, is often conclusive.
• Specific gravity: Hydrostatic weighing yields values of 2.44–2.62 for serpentine, well below jadeite (3.25–3.36) and nephrite (2.90–3.03).
• Refractive index: The refractometer reading of approximately 1.49–1.57 for serpentine differs clearly from jadeite (1.654–1.667) and nephrite (1.600–1.627).
• Infrared spectroscopy: FTIR spectroscopy provides a definitive mineralogical fingerprint, distinguishing serpentine-group minerals from both jadeite and nephrite with high confidence. This method is routinely employed by major gemmological laboratories.
• Chelsea colour filter: Chromium-bearing serpentine may show a reddish reaction under the Chelsea filter, similar to some jadeite, so this test alone is not diagnostic.

Major gemmological laboratories — including the GIA Gem Laboratory, Gübelin Gem Lab, and SSEF — routinely identify and report serpentine in submitted jade parcels and carvings, issuing reports that specify the material as serpentine rather than jade.

Trade Usage and Disclosure Standards

The Federal Trade Commission (FTC) in the United States and equivalent consumer-protection frameworks in other jurisdictions require that the word "jade" used without qualification refer to jadeite or nephrite. Applying the term to serpentine without clear disclosure — such as "serpentine jade" or "serpentine (Honan jade)" — constitutes a misrepresentation. The International Colored Gemstone Association (ICA) and the American Gem Trade Association (AGTA) similarly require accurate species identification in trade nomenclature.

In practice, the term "Honan jade" persists in several contexts: older estate and auction descriptions where the material was not tested at the time of cataloguing; certain Asian domestic markets where regional trade names carry cultural weight; and antique carvings where the historical attribution is itself part of the object's provenance record. Responsible dealers and auction houses now typically append a gemmological qualification — "serpentine, known in the trade as Honan jade" — when the material has been tested and confirmed.

The price differential between serpentine and genuine jade is substantial. Fine imperial jadeite can reach tens of thousands of US dollars per carat for top-colour cabochons, while serpentine carvings of comparable size trade for a small fraction of that figure. This disparity makes accurate identification essential for buyers, insurers, and estate appraisers alike.

Aesthetic and Collecting Considerations

Assessed on its own merits rather than against the standard of true jade, serpentine from Henan can be an attractive and historically significant carving material. Antique Chinese carvings in serpentine — brush rests, snuff bottles, belt hooks, and ritual objects — have legitimate art-historical value independent of their mineral identity, and some collectors specifically seek well-carved serpentine pieces for their aesthetic qualities and affordability. The softness of the material (Mohs 2.5–4) means that carved surfaces are more susceptible to abrasion and surface dulling over time than equivalent jadeite or nephrite pieces, and serpentine should be stored and handled accordingly, away from harder stones and abrasive surfaces.

Care should also be taken with cleaning: serpentine is sensitive to acids, including mild household cleaners, which can etch polished surfaces. Warm water and a soft cloth are the recommended cleaning method for serpentine carvings and ornaments.

Further Reading

• GIA Gem Encyclopedia: Jade
• GIA Gem Encyclopedia: Serpentine
• AGTA Gemstone Information