630 PROF. G. F. F. ULEICH ON THE 



the banks of the Gorge Eiver, and the ground covered by the mineral- 

 leases applied for with the view of working the nickel is marked in 

 red on the lithograph-plan enclosed [see the indication on the 

 sketch-plan, p. 624]. These deposits have evidently been brought 

 across the saddle into the Gorge Kiver from the Olivine Range 

 at the back of it." 



As, in consideration of the large extent of the peridotite or serpen- 

 tine rocks, it seemed to me very unlikel}^ that the occurrence of the 

 mineral should be confined to the Gorge Kiver only, I specially 

 requested Mr. R. Paulin, before he set out on his exploring and 

 prospecting trip, to look out for the alloy in the olivine and serpentine 

 rocks and the drift of the rivers and creeks he prospected. The 

 results of his examinations in this respect are given on the sketch- 

 plan previously alluded to (p. 624), — the many places where he found 

 Awaruite being marked by black crosses. In his explanatory letter 

 to me he states as follows : — "I have found small specks of nickel 

 in the rocks of various localities, most conspicuous at Silver Creek 

 (a tributary of the Jerry River rising in the Red-Hill Range), and I 

 think that it occurs throughout the whole formation. The free 

 nickel found in different river-beds is much coarser than any I 

 have seen in the stone. On the Red Hill itself 1 found nickel 

 2400 feet above sea-level." The area of distribution of the Awaruite 

 is thus by Mr. Paulin's observations proved to be far more extensive 

 than first imagined, and it may be larger still, for I see nothing 

 unreasonable in his belief that the mineral occurs in the impreg- 

 nated matrix throughout the whole extent of the peridotite and ser- 

 pentine rocks ; and, inferentially, in the liberated state in the drifts 

 derived therefrom. The gradual gathering of practical proof of this, 

 however, will, I fear, take a long time, owing to the great hardships 

 and dangers connected with prospecting in that wild, inhospitable 

 district. The supposed recognition of Awaruite distributed through 

 the rock will also, in many cases, not be free from doubt, unless the 

 specks be detached and specially tested. This is on account of the 

 smallness of the specks, and their frequent association with, and 

 general resemblance in colour to, grains of pyrite, which may there- 

 fore be easily mistaken for it. The simplest test in the case of de- 

 tached specks is by application of the magnet, which energetically 

 attracts the Awaruite specks, but leaves those of pyrite unaffected. 

 The malleability of the specks affords another proof of their identity. 



EXPLANATION OF PLATE XXIV. 



Figs. 1, 2, 3, are drawn in ordinary light from thin slides cut in different direc- 

 tions from a piece of medium-grained Peridotite fj-om the Red Hill ; 

 magnified 20 diams. 



Fig. 1. In this both the Olivine and Enstatite are remarkably clear, and the latter 

 is only distinguishable from the former by a faint brownish-yellow tint 

 and parallel cleavage-cracks. The large cross-shaped grain in centre 

 of the figure is Enstatite, showing between crossed Nicols in patclies 

 a slightly curved fibrous structure with wavy extinction parallel to the 

 fibres. Polarization-colours yellow, orange to brown. At lower right- 



