An " Ovenstone'\fro)n Zinal, Canton Valais. 113 



not to be A^evy uniform, some containing more C O2 than others. 

 Tlie amount of HjO and Ni also varied, the latter being in a second 

 sample only 0-5, and in a third not more than 25 per cent. The 

 first variation is no doubt due to the fact that the carbonate occurs 

 in small veins. That of the Ni accords with what was observed 

 in the Riffelhorn serpentine, but here I fail to discover awaruite, 

 and conclude that all the nickel must be present as a silicate.^ 

 So far as one can judge from rough calculations, the specimen 

 analyzed above might consist of quantities, approximately equal, 

 of talc, tremolite, and a chlorite. 



Through the kindness of Professor W. Ramsay, F.R.S., I have 

 had the opportunity of examining a specimen of noumeite ^ from 

 New Caledonia, a mineral to which a passing reference was made in 

 the paper by Miss Aston and myself on the EifFelhorn serpentine. 

 The hand-specimen has a somewhat " waxy " aspect and lustre ; in 

 colour is a rather variable emerald-green,^ mottled with spots, 

 diverse in size and quantity, of a dark, soraewhat purplish tint, 

 giving the mass a slightly brecciated aspect. This last becomes 

 more distinct on microscopic examination. The apparent fragments 

 are " flaky " in outline, and differ much in size, the larger being 

 darkened by the presence of a brownish dust, but all are moi-e 

 distinctly yellow in colour than the ground-mass. They consist 

 of a fibrous or flake-like mineral, which exhibits a very faint 

 pleochroism and bright polarization tints. The small size and 

 entanglement of the flakes make it difficult to ascertain their 

 extinction angle, but if not straight this angle is very small. 

 Possibly more than one mineral is really present. The ground - 

 mass in which these patches and spots occur is fairly uniform in 

 aspect, just tinged with a greenish yellow, and now and then 

 traversed by ligliter-coloured, more compact-looking veins. With 

 crossed nicols it appears as a dark ground speckled with whitisli 

 granules or flakelets. Probably, however, it consists of a densely 

 matted mass of doubly refracting minerals, allied to serpentine. 

 The aspect of the whole suggests that fragments of a badly 

 preserved, perhaps rather exceptional serpentine, are imbedded in 

 a kind of steatite. Analyses and a description of noumeite are 

 given in Dana's " Mineralog}',"* where it is counted, with garnierite, 

 as varieties of genthite. All three are described as apple-green 

 minerals, varying from light to dark, rather soft, and non-crystalline. 

 Professor Liversidge, who has made special studies of both,^ states 

 that garnierite differs mainly from noumeite in being much less 

 common, lighter in colour, adhering to the tongue, and falling to 

 pieces in water. Microscopic examination of the above-named 



* At Ayer, a hamlet about an hour's walk do-mi the valley, are old nickel-mines, 

 hut as I did not anticipate this mineral turning up here, I did not vii5it them. 



'^ Named from Noumea, capital of New Caledonia ; described by Professor 

 Liversidge, Proc. Roy. Soc. N.S.W. 1875, p. 75 ; Journal, 1881, p. 227.^ 

 3 This part is not imlike chrysocolla, but the colour is rather brighter. 



* Ed. 1892. 



5 Proc. Eoy. Soc. N.S.W. , ut supra. 



DECADE IV. VOL. IV. NO. III. 8 



