BY EDWD. B LINDON, A.R.S.M. 51 
Iron PyritEs—Comp. Fe S,, but liable to have part of the iron 
replaced by various other metals as nickel, cobalt and copper. 
This is a mineral of very wide-spread occurrence and of 
manifold associations, nor is it my intention to do more than 
mention some of greater interest, prefacing my remarks by stating 
that pyrites occurs in rocks of every age, from the oldest to the 
most recent formations. 
In the Tinaroo district pyrites is a very common associate of 
cassiterite, as in the Leviathan, where these two minerals occur 
with wolfram and fluorspar. On the Hodgkinson goldfield auri- 
ferous pyrites accompanies sphalerite and galena, and similarly 
on Ravenswood. On Charters Towers auriferous pyrites is the 
principal mineral mined for, galena, sphalerite, and sometimes 
chalcopyrite being generally its associates. In the Bryan O’Lynn 
on this field auriferous pyrites occurs in granite, the rock assaying 
about 2 dwts. to the ton, and in No. 1 Claim on the Old Identity 
Reef pyrites containing visible gold has been met with. In the 
Allendale lode, Chowey Creek, Wide Bay district, iron pyrites 
occurs with arsenical pyrites, galena, and sphalerite, the ore 
carrying both silver and gold. On the Norton goldfield and in 
the Rockhampton district, iron pyrites of an auriferous nature is 
of frequent occurrence, one association at the Union Gold Mining 
Co.’s lease, Rockhampton, being especially worthy of note, as in 
the 172 ft. level the pyrites occurs with black schorl or tourmaline. 
On the Nebo goldfield pyrites takes the form of pentagonal 
dodecahedra, and on Ravenswood specimens in chert are crystal- 
lized as hexakisoctahedra. Iron pyrites also abounds in the Mount 
Perry and Cloncurry districts, whilst in the Etheridge district a 
very richly auriferous pyrites occurs, mixed, as I believe, with 
marcasite ;* this pyrites is often of a very dark colour, and 
frequently occurs in clusters of cubical crystals; I think a 
complete analysis of this pyrites would prove interesting, and I 
shall hope to make such when I can get a fresh specimen, as 
decomposition commences after leaving this pyrites exposed for 
any length of time to the atmosphere. 
CHALCOPYRITE—COPPER PyRITES—Comp. probably Cu, 5 + Fe 
» Fe S,. 
This is another mineral of general occurrence, the copper 
carbonate stains so frequently to be seen on various rocks being 
due to the decomposition of this sulphide. 
*Vide Marcasite. 
