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Chief Petrologist, N.Z. Geological Survey, Wellington.

THE CORRECT USE of the terms greenstone, nephrite, bowenite, and jade, has recently been the subject of correspondence in this Journal (Vol. 65, pp. 174-5). It may assist ethnologists, therefore, if the mineralogical aspects of the problem are stated.

The jade-like artifacts of the Maori include two distinct mineralogical species—nephrite and bowenite. The nephrites are composed essentially of an amphibole of the tremolite (Ca2Mg5(OH)2Si8O22)—actinolite (Ca2(Mg, Fe)5(OH)2Si8O22) series, whereas bowenites consist essentially of serpentine (Mg3(OH)4Si2O5). The Maori nephrites and bowenites are fully described by Finlayson (1909, pp. 361-2; 367-8) and Turner (1935, pp. 188-94; 198-205). The Maori names for nephrite and bowenite are generally considered to be pounamu and tangiwai, respectively. Ethnologists must decide the meaning of “greenstone,” but it appears to be a group term applied to both the nephrite and bowenite artifacts of the Maori, a conclusion with which both your correspondents agree. Jade is a group term and in a strict sense includes only nephrite and jadeite. Jadeite is a pyroxene mineral (NaAl Si2O6) mineralogically distinct from both nephrite and bowenite. It is clear therefore that greenstone (as here used) and jade are not synonymous. Nephrite is included in jade but bowenite is not.

It would appear that there is need for a general group term to cover all jade-like artifacts irrespective of mineralogical composition. Jade, used in a broad sense, might have been suitable, as mineralogists almost invariably use the more precise term jadeite and nephrite, but gemmologists insist that jade be restricted to jadeite and nephrite (Spencer, 1947, p. 209; Smith, 1949, p. 414). It is thus incorrect and misleading to include bowenite artifacts in descriptions of “Maori Jade” as has been done by Webster (1948) and Ruff (1950). “Maori Greenstone” is a suitable title, however, if the definition of greenstone given earlier is the accepted one. Greenstone, in fact, is the only term in common use that could be employed as a general group term. Presumably greenstone would have included jadeite if that mineral had occurred in New Zealand and been used by the Maori. That greenstone is used overseas as a group term to include jadeite is clearly indicated by Forde (1930) whose paper is entitled “On the use of greenstone (jadeite, callais, etc.) in the megalithic culture of Brittany,” and by Crawford (1949, p. 170) who says, “One of the finds was part of one of those greenstone (jadeite) axes . . . which are usually thought to originate in Brittany.”

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To summarize the position:—

• (a) Precise scientific description demands the use of the terms nephrite, jadeite, and bowenite, rather than the mineralogically ambiguous jade and greenstone.
• (b) Jade is a group term referring only to jadeite and nephrite.
• (c) Greenstone covers both the nephrite and bowenite artifacts of the Maori.
• (d) There is need for a general group term to cover all jade-like artifacts irrespective of mineralogical composition. Greenstone appears to be the only common term at all suitable and it is suggested that ethnologists consider (or confirm) the use of the term in this manner. Where the mineral variety is known, it could be shown in brackets, e.g., greenstone (nephrite).

REFERENCES.
• CRAWFORD, O. G. S., 1949. Editorial Notes. Antiquity, 23:169-71.

• FINLAYSON, A. M., 1909. “The Nephrite and Magnesian Rocks of the South Island of New Zealand.” Quart. J. Geol. Soc. Lond., 65:351-81.
• FORDE, C. D., 1930. “On the use of greenstone (jadeite, callais, etc.) in the megalithic culture of Brittany.” Jour. Roy. Anthr. Inst., 60:211-34.

• RUFF, E., 1950. Jade of the Maori. Gemmological Association of Great Britain, London.

• SPENCER, L. J., 1947. A Key to Precious Stones. 2nd ed. Blackie, London.
• SMITH, G. F. H., 1949. Gemstones. 10th ed. Methuen, London.

• TURNER, F. J., 1935. “Geological Investigation of the Nephrites, Serpentines, and Related ‘Greenstones’ used by the Maoris in Otago and South Canterbury. Trans. Roy. Soc. N.Z., 65:187-210.

• WEBSTER, K. A., 1948. The Armytage Collection of Maori Jade. Cable Press, London.