Cox.—On the Mineralogy of New Zealand. 891 
is white, with glossy conchoidal fracture like milk-opal, or with earthy 
fracture like magnesite. At Te Tarata siliceous deposits in terraces cover 
about three acres of land. 
2 ALUMINA. 
Corundum, Aj.—Dr. v. Haast mentions the occurrence of the variety 
sapphire from the western slopes of the Southern Alps (Geol. Rep., 1870- 
71, p. 24), and in August, 1871, Captain Hutton brought another specimen 
from Collingwood, which is now in the Colonial Museum. It is described 
in the Seventh Museum and Laboratory Report, p. 18, as follows :—"' A 
rough sapphire, sent by a digger, who found it with alluvial gold at Colling- 
wood, Nelson, is the first discovery of this precious stone in the colony. 
The specimen, which weighs 996:9 grains, is in the form of a water-worn 
pebble, remarkable on account of its deep blue colour on the fractured sur- 
face, and its great weight; but it is so traversed by fissures as to be of no 
value as a gem. Its specific gravity is 9:869." 
Now-wETALLIO MiwERALs.—Class VI. 
Silicates of magnesia and lime, hydrous and anhydrous. 
Silicates and | Silicates of alumina, hydrous and anhydrous. 
Aluminates. | Aluminates of magnesia and glucina. 
Silicates of glucina, zirconia, thoria, and yttria. 
AxnmypRoUs SinicarEs or Maenesia AND Lime. 
Wollastonite, Ca Si.—8pecimens of a massive form of wollastonite were 
collected from the Dun Mountain by the late Mr. E. H. Davis in 1871, and 
are now in the collection of the Colonial Museum. They have been de- 
scribed and analyzed by Mr. Skey, who reports (Col. Mus. & Lab. Rep. vi., 
p. 15) that the four specimens examined had the following composition :— 
$ 2. 8, 4. 
Silica 48°01 49°30 50°62 58°80 
ime 46:20 45:01 44:88 24:60 
Magnesia traces ‘80 traces 1:60 
umina ys i 1:41 1:84 | 12-20 
Iron oxide ica .. traces traces 1:64 
Loss ae - 1 traces 1:40 
Water .. 2 i ED 1:39 1:02 1:40 
100-00 100-00 100-00 100-00 
The iron oxide in Nos. 3 and 4 is the protoxide, and No. 4 contains traces 
of chromium. 
They are massive, confusedly erystaline, colour pure white, lustre 
pearly inelining to vitreous on certain fractures, easily fusible to glassy 
bead with no soda reaction. Easily decomposed by hydrochlorie acid with 
the formation of gelatinous silica ; hardness 4 to 5. No. 4 is an impure 
