A diverse range of mineralisation, including porphyry and epithermal deposits, intrusion-related gold and other metal deposits, iron oxide-copper-gold (IOCG) deposits and orogenic gold deposits all have linkages to crustal growth and magmatic arcs. Furthermore, all of these deposit types are associated with fluids containing H2O, CO2 and NaCl in varying and differing proportions. In all cases, it can be argued that magmas are a key source of hydrothermal fluids for these types of mineral system, and that subduction processes are critical to controlling fluid chemistries, the metal-bearing capabilities of the fluids and depositional processes. The differences on typical/bulk fluid chemistries between deposit types can be explained in part by differences in the P-T conditions of fluid segregation from its magmatic source. The most significant control here is the pressure at which fluid forms from the magma as this has a strong effect on fluid CO2/H2O values. This is clearly exemplified by the rare occurrence of readily detectable CO2 in deep porphyry systems (Rusk et al., 2004). On the other hand, fluid Cl contents (which strongly influence its base metal carrying capacity) are very sensitive to the magma's bulk composition. However, only some subduction-related magmas are fertile, and the differences do not seem to be due solely to variations in effectiveness of depositional processes. So what controls the volatile content of the magmas? Isotopic and other evidence, in particular for S and Cl, shows (unsurprisingly) that the greater contents of these elements in arc magmas compared to other melts is due to contributions from subducted materials, although there may be additional, lower crustal sources of Cl. Variations in the budget of volatiles subducted may thus play a role in controlling the chemistry of magmas and associated hydrothermal fluids, but variations within individual arcs suggests that again this is not the entire story.

The enquiry into this mine resulted from an application by the company for a loan from the Commonwealth to carry out exploration and development. The Tindalls Gold Mine has not been examined by the Bureau and unless this is done no definite statement about the ore possibilities of the property can be made. However, from past reports it seems likely that the deposit has a chance of producing a large tonnage of ore. Under present conditions and with the mining methods now employed, it is extremely doubtful whether ore of this grade could be mined at a profit. The ore reserves, mining, milling, costs, and general financial outlook with respect to the mine are discussed in this report.

The analyses of some Australian iron ores was undertaken. The results of these analyses are set down in this report. Results are given for each deposit by state.

The geology and ore reserves of the dolomite deposit near Wall's Siding are discussed in this report. The report should be read in conjunction with the report on "Limestone and Dolomite Deposits at Cow Flat and Wall's Siding, New South Wales" (Record 1947/090).

The operational history, orebody, workings, grade, tonnage, and financial considerations relating to the Chesney mine are discussed in this report. Two geological plans are included.

At the request of Mr. G. Lindesay Clark, Deputy Controller of Minerals Production, estimates have been made of the grade of ore likely to be delivered to the mill during the next two years under conditions of half-scale production. The methods of estimating tonnage and grade, as well as the resultant estimates, are discussed in this report.

"Greisen Lode" is the name given locally to the foot-wall section of a wider mineralised zone, which will be referred to as the Greisen Orebody in this report. Mining operations have been carried out by tributers in recent years on several portions of the orebody, namely, stoping from the Main Tunnel, stoping from an adit-crosscut driven from the No. 4 Gossan Bench, and some stoping operations from a level above the latter bench. During the past three months a level has been driven for 260 feet westwards from the Main Tunnel to prospect the orebody at this level and develop it for mining. Over the past few weeks a detailed geological examination of the orebody has been made and the area involved mapped on a scale of 20 feet to an inch by means of plane table and alidade.

The Wilks Creek wolfram mine is situated in the parish of Steavenson, county of Anglesey in central Victoria. It is approximately 4 miles south from the small town of Marysville, a popular tourist resort, and 61 miles by road northeast from Melbourne. Underground and surface mapping was carried out on the 23rd and 24th November, 1943, with compass, tape and Abney level. This report comprises an overview of production history, general geology, economic geology and ore reserves.

This progress report follows a general report on the Wymah field by N.H. Fisher and C.L. Knight, submitted in June, 1942. It contains details concerning the development, ore structures, and mineral reserves of the Wymah wolfram mine.

A review of mineral exploration activity in Australia for 2009. This extended edition includes coverage reported in the shorter edition.