Gems from Around the World
Although North American and Canadian process industry personnel are most familiar with Kason separators, personnel in other countries are on finding practical uses for them. One example is Argyle Diamond Mines in Western Australia. It has found that 30 inch diameter VIBROSCREENS serve well for acid dissolution of gangue on the diamonds in addition to rough sizing operation.
Located in the Kimberley region about 1,243 miles north of Perth, Argyle is one of the world's biggest diamond mines, yielding more than 25 million carats a year .
Six of the VIBROSCREEN separators operate on site and two machines are used at the Balcatta laboratory. And the ninth unit has been built for a special purpose for Argyle Diamond Sales .
Prior to diamond grading, the diamonds are sorted to size in 18 different groups. Normally, this takes place a 200 mm diameter screen. Screen plates are of 0.55 mm stainless steel with special perforations having hole diameters controlled to a + 0.001 inch tolerance.
The screen plates are supported by specially profiled 6 mm plate spiders and ball trays are fitted to each deck that have either Nordel or nylon balls. The balls impact on any near size diamonds jammed in a hole.
According to Warman International, the Australian licensee of Kason equipment, the screen classifiers are playing a significant part in the Argyle venture which has been developed at a cost of $430 million (Australian).
Screen Tips - Volume 3, Number 1 March 1988
Detail of the diamond sorter screen.