This report was prepared by the Mineral Economics Section. Part 1 deals with the production of opal and includes sections on the history and present operations in the industry, production and overseas trade statistics, and the types of mining tenures at present available to opal miners. The fields at present being worked are described and the factors which affect production are discussed. Part 2 deals with the marketing of opal and includes sections on the cutting and preparation of stone, markets at home and abroad, and the various factors affecting trade. A number of proposals for improving trade and trading conditions generally are discussed, and the report concludes with a list of references in literature, two graphs showing the value of opal produced in each State and the whole of Australia, from 1890 to 1947, and a map of Australia showing localities mentioned in the text.

The second drill hole on the area of the Dapville No. 1 anomaly has been completed and some details of the results are given in this report. Following the discovery of this and other magnetic anomalies of low intensity in the course of surveying, there is a need for the determination of priority on the part of the operating company, in the testing of these anomalies. The principal purpose of this report is to draw further attention to the Peak magnetic anomaly and to discuss various factors which the company may desire to take into consideration in the determination of the priority question mentioned above.

This report describes the results of a micropalaeontological examination of samples recovered from the depth of 200-250 feet from Bondsprings station.

The eastern boundary of the area (the western boundary of D.C. 22) from Peerless Avenue to Ocean Street, was bored in August, 1947. The remainder of the area was bored in April, 1948. Bore-holes were put down to water level, using post-hole digger. Samples were dried and weighed and their volumes determined. The samples were then concentrated by panning, and the weights and volumes of the concentrates were determined. The percentage composition of a composite sample of concentrates from each bore line was determined by grain counting. The data collected and the findings of the investigation, including estimates of the quantities and grades of heavy mineral concentrates, the quantities of overburden and the quantities of each of the heavy minerals, are tabulated in this report.

This report describes the results of the micropalaeontological examination of five rock specimens from the Kimberley Basin.

An investigation into the possibility of providing additional water supplies to the township of Tennant Creek was carried out by the Department of Works and Housing. A request was made to the Bureau in March, 1947, to carry out a geological examination of possible dam sites in the Tennant Creek area. A preliminary inspection of two possible sites was made on 5th June, and a detailed plane table survey of both sites was carried out on 6th and 7th July, 1947. The location, access, topography, general geology, engineering geology, and recommendations for future investigation and work 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.

This report comprises notes on the occurrence of ceramic clays in Australia. Data concerning occurrence and grade is provided for each deposit by state.

This record describes the results of a micropalaeontological examination of samples collected from the depth of 30 to 1445 feet down.

This report describes the results of a micropalaeontological examination of two rock samples from the Kimberley district.