Cox. — On the Mineralogy of New Zealand. 439 



Bog Iron Ore is another form of hydrous hematite which is found at 

 several locahties in New Zealand. It is, generally speaking, of a porous 

 character, and varies considerably in its composition. It has never yet 

 been found in any considerable mass, and is seldom of much value on 

 account of the phosphorus which most samples contain. 



Analyses have been made of samples from Spring Swamp, Whangarei ; 

 Wainui-o-mata, Wellington ; Carterton ; Eangitikei ; Stoke, Nelson ; and 

 Oroua Downs ; in which the percentage of metallic iron varies from 19 to 51. 



Spathic Iron Ores, Fe C. — The massive forms of these ores, which are 

 essentially carbonate of iron, are very widely distributed in New Zealand, 

 being, as a rule, associated with the cretaceo-tertiary and coal formations. 

 Bands of clay ironstone, about 2 feet thick, occiu- in the Waipara District, 

 and another band of sandy clay iron ore, 10 feet thick, is mentioned by Dr. 

 Haast in the same locality (Geol. Kep., 1870-71, p. 11). Ii-onstone boulders 

 are found in the Kakanui Eiver which have been derived from the concre- 

 tionary greensands. Valuable deposits of clay-band ironstone occur near 

 Mount Somers and in the Malvern Hills, associated with coal, and further 

 deposits are also found near the Abbey Kocks, Westland. Associated with 

 the coal measures on the Twelve-mile Beach north of the Grey Eiver, and 

 thence inland, valuable deposits of spathic iron ore occur as lenticular 

 masses and concretions in the shales. They are also notably developed 

 in the Nine-mile Creek in the same district. • They are again found at 

 Jenkins Hill,^ Nelson, and at the CoUingwood Coal-mine, where a bed of 

 black-band ironstone also occurs, and another instance of its occurrence 

 is at the Baton Eiver, Nelson, in the cretaceo-tertiary formation. 



In the North Island, beds of spathic iron ore have been found in the 

 same formation, at the Miranda Colliery, inland of Taranaki, at the Mana- 

 watu Gorge, at Wangaroa and Eaglan. In most of these localities the 

 ironstones are fossiliferous, and contain numerous and well-preserved 

 impressions of dicotyledonous leaves. 



Further deposits of spathic iron ore also occur in the Mataura series, 

 having been discovered by Mr. McKay, in the Cairn Eanges, Malvern Hills. 

 They occur as strings and lenticular patches, with beautifully-preserved 

 fossil ferns, and are of considerable importance. 



Analyses of ores of this description have shown that they contain from 

 8'53 per cent, to 46'06 per cent, metallic iron, and the details of these will 

 be found in the works above cited. They are all brown, sandy-looking ores, 

 and are specially valuable on account of the ease with which they are 

 reduced. 



Siderite, Fe C. — The occurrence of this mineral in cavities of the con- 

 torted schist of Otago is mentioned by Dr. Hector (Jurors' Eep. N.Z. Ex., 



