Metallurgical assessment is commonly conducted using gravity, magnetic and/or electrostatic separation. The minimum mass required for this detailed mineralogical assessment will often necessitate compiling multiple samples into HM weighted composites for analysis.
- Once the mineralogy and geology of the resource is better understood, larger scale bulk samples are collected from the deposit. These bulk samples represent different zones or mineral assemblages within the deposit and allow Iluka to understand the metallurgical variability within a deposit. The bulk samples are treated at Iluka’s metallurgical test facilities at Capel, Western Australia.
Of particular importance during the metallurgical assessment is the determination of the proportion of primary and secondary ilmenite within the ilmenite spectrum. This determines which markets the ilmenite can be sold into. Alternatively, whether the ilmenite is suitable for upgrading via either the synthetic rutile or Titania slag routes. Metallurgical testing has been developed within Iluka to determine not only the amount of these two types of ilmenites, but also their qualities and suitability for the respective end markets. Based on the quality of the ilmenite Iluka then uses its pilot plant facilities at Capel to determine, on a laboratory scale, if the ilmenite is suitable for synthetic rutile production and is also able to predict the quality of synthetic rutile which can be produced from an ilmenite from a specific deposit, or a blend of ilmenites from a variety of deposits.
- Metallurgical testing is also designed to provide predictions of the product quality of both rutile and zircon products.
For rutile, important impurities such as iron, zirconium, silica and tin are assessed, while for zircon, alumina, iron, titanium, thorium and uranium are measured. The whiteness and opacity of the glaze in a test tile is also determined for zircons from different deposits, to determine how suitable these zircons will be for the ceramics market. These tests are conducted in Iluka’s tile testing facilities at both Narngulu in Western Australia and Hamilton in Victoria.
Iluka’s zircons are internally ranked and mineral processing mechanisms have been developed by Iluka to control the ceramic qualities of zircon to ensure consistency of product quality during production. Zircon products are also produced for non ceramics end applications.