At BHP's Marillana Creek, production has begun in a satellite operation of pisolitic
limonite at a rate of around 3 Mt/y, but BHP has approval to expand to 10 Mt/y as market demand for this type of ore increases.
The upper horizon comprises of upper 3m thick oolitic or pisolitic
laterite and lower 4m thick bauxitic material.
Carbonates occur in different forms such as hardpans, nodular or pisolitic
layers, mottled carbonate-rich layers, and calcareous fine earths (Milnes and Hutton 1983).
, dehydrated hardcap bauxite, often forming a surface hardcap layer 2 metres thick .
The predominant soil type in the areas to be mined and in restored areas is a Brown Kandosol (approximately 600 mm deep) (Isbell 2002) that originally overlies a pisolitic
Numerous round, ocherous patches of powdery, pale yellow, pisolitic
anatase are commonly found embedded in the surface of latestage gray quartz and adularia crystals.
Yandi has a measured resource of 320 Mt of high-grade pisolitic
ore particularly suited for sinter feed and will produce 5 Mt/y.
Another significant result of the mapping was the recognition of cemented detrital hematite-goethite outcrops and the presence of pisolitic
ironstone gravels which indicate potential for channel iron deposits formed by the weathering and remobilisation of the altered BIF.
The soil profile ranges from 0.2 to 0.8 m deep and overlies pisolitic
bauxite (from 1 to 9 m deep) (Schaap 1985).
Further some negligible lateritic and pisolitic
bauxite of Indus Formation of Latest Cretaceous to Cretaceous-Tertiary boundary found just below the Early Paleocene Hangu Formation (2-5m; coal, quartzose sandstone, shale; synonym Patala) which is followed by Late Paleocene to Early Eocene Sakesar Limestone (115m; synonym Margala Hill and Lokhart Limestones: rubbly nodular/conglomeratic type just like the Dungan Limestone of Sulaiman and Kirthar basins).
A recent round of pisolitic
soil sampling has been carried out over the Napier Prospect and analytical results are expected to be received during the September 2010 quarter.
(1994) as: `indurated zones of unconsolidated materials (soils, sediments) cemented by secondary palygorskite (generally [is greater than] 65%) that may display characteristic structures, such as nodular, laminar or pisolitic