D’Aguilar Gold’s wholly owned subsidiary Ridge Exploration has announced the key findings of a six-month preliminary study and field reconnaissance program. Ridge was incorporated to apply for exploration licences for sedimentary iron ore over parts of the northern Surat Basin in Queensland and other areas where previous work has identified sedimentary iron ore development with over 40% Fe content. It is close to worldclass coal deposits and excellent infrastructure.
D’Aguilar Gold notes that, “while over the past 40 years the mining industry has concentrated on the exploitation of haematite ores grading over 55% Fe, it has been overlooked that for most of the history of the iron and steel industry (many centuries) iron ore grading 35+% was the accepted standard. These lower grades are still mined throughout North America and Europe. Given that the Ridge target areas are situated adjacent to massive coal and gas fields, and given relatively high prices for iron ore, there is potential for lower than currently used grades of iron ore to be profitably exploited even bearing costs of beneficiation.”
The tenements are held or applied for by Ridge Exploration and other D‘Aguilar Gold subsidiaries including Eastern Uranium and Central Minerals in Southern Queensland. These tenements sit astride major existing or planned railway lines with access to several Queensland ports.
The main areas of iron potential have been targeted in two related formations. In the central southwest of Queensland, the Westgrove Ironstone Member is contained within a sandstone belt starting approximately 100 km north-northwest of Mitchell and snaking for 180 to 45 km west of Taroom. In eastern southern Queensland and Central Queensland, the Oolitic Ironstone Member of the Evergreen Formation has been targeted from Taroom, Wandoan, to the Mundubbera, Eidsvold and Monto areas.
Banded and concretionary ironstone beds of the Westgrove Ironstone Member to an indicated thickness of 10 m have been located in outcrop extensively across the western exploration areas. The Fe content on representative samples of the indicated higher grade beds ranged from 29 -49%, with many samples over 40%. The phosphorous content ranged from 0.25 to 0.5%.
Exposures of the Oolitic Ironstone Member in the eastern tenements were also extensive, with an inferred thickness of 6-10 m and a similar range of iron grades to the western tenements. Phosphorous levels were generally lower. The best representative sample graded 49.9% Fe and 0.01% P.
A total of sixteen (16) project areas have been identified for detailed assessment. From west to east these are: Mt Owen, Crystalbrook, Darkwater, Ogilvie, Westgrove, Stillwater, Currajong, Mt Rose, Johnson Creek, Cadarga (Eastern Uranium), Koko (Central Minerals), Eidsvold, Abercorn, West Emerald, Denham Range, and Duaringa/Middlemount.
As exploration tenements proceed to grant a second phase exploration program will be undertaken on each of the identified project areas. This will include further sampling and mapping of ironstone outcrop and exposure, and collection of representative bulk (20 kg) samples which will be used for initial metallurgical testing to determine the best methods to upgrade ore if required.