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variety called, from the Swiss valley of Tremola, Tremolite. 
Subsequent analyses of some of the dark green jade of New 
Zealand have shown that this also may have a similar compo- 
sition, and may be referred to the green variety of hornblende 
called, from the radiated structure which it characteristically 
presents, Actinolite, Both these kinds of jade are therefore 
hornblendic or amphibolic minerals, similar in chemical com- 
position to well-known minerals occurring abundantly in 
Europe and elsewhere, but differing from them in certain 
physical characteristics. No forms of tremolite or of actinolite 
are known in Europe to which the designation of jade can 
fairly be applied. 
The specific gravity of this hornblendic jade, distinguished 
by Damour as Oriental Jade , is about 3. Mr, T. Davies, of 
the British Museum, who has determined the density of upwards 
of a hundred specimens from New Zealand, gives the limits 
between 3*00 and 3*02.* It may seem trivial to dwell upon 
this point, but it will be presently seen that specific gravity 
offers a valuable means of diagnosing the jades. 
Some other examples of New Zealand jade examined by 
Damour yielded very different proportions of lime and magnesia, 
and the analyses lead to a formula more like that of augite or 
pyroxene than of hornblende. In physical properties it closely 
resembles the Oriental variety, but differs in having a specific 
gravity of about 3*18. It appears to be a rare mineral, and as 
it is known only from New Zealand and the Marquesas Islands, 
it has been distinguished as Oceanic Jade.'f It must not be 
forgotten, however, that most of the jade of the Pacific Islands 
belongs to the hornblendic and not to the augitic form. 
On examining a sample of green jade, about sixteen years 
ago, M. Damour found so great a difference in its composition 
from that of either the Oriental or the Oceanic nephrite, that 
he proposed to regard it as a distinct mineral under the name 
of Jadeite.% It is a silicate of aluminium, sodium, calcium, 
magnesium, &c. Its specific gravity varies between 3*28 and 
3*35, and is therefore higher than that of jade : it is also 
harder, and hence jadeite will scratch a piece of ordinary j ade. 
Damour placed this mineral near to Wernerite. It is this 
substance which, as mentioned above, occurs in Yunnan, and is 
known as feit-sue. Many of the celts found in Brittany and in 
* u Notes on Jadeite and Jade.” By Thomas Davies, Esq., F.G.S. Appendix 
to Lees translation of Keller’s “ Lake Dwellings,” 2nd ed. vol. i. p. 683. 
t “ Sur la composition des haches en pierre trouvees dans les monuments 
celtiques et chez les tribus sauvages.” Par M. Damour. Part II. “ Oomptes 
Rendus,” t. lxi. 1865, p. 357. 
\ “ Notice et analyse sur le Jade vert: reunion de cette matiere minerale 
a la famille des Wernerites.” “ Comptes Rendus,” t. lvi. 1863, p. 861. 
