Glen Korstrom
Northern News Services

NNSL (Sep 03/99) - Before any company goes forward with a diamond mine, there is much drilling, sand sampling and analysis.

This is the case with Ateba Mines and testing from a site about 500 kilometres northeast near Kennady Lake.

"We've recovered indicator minerals before so we're just tightening up the samples now to get a better idea of what's going on," says A.C.A. Howe consultant geologist Jim Bryce, who was in Yellowknife last month sifting through till samples with a screening machine.

"It's kind of like panning but a lot more scientific."

Bryce had been in the North from Toronto for a couple of weeks and started the stint by taking 121 till samples from the possible diamond site.

Then came screening.

"You take a bag with 100 pounds of till and shake it and pass it through screens and separate the clay and different sizes of sand," he said.

Sand samples are separated into three different bags: .3 to .5 millimetres; .5 to one millimetre and one to four millimetres.

Anything larger than four millimetres is inspected by hand and usually thrown away.

And about 70 to 80 per cent of the till sample is clay that just gets washed away during the screening process.

Once the sand passes through the screening phase, Bryce and his partner, Phil Jackson, put it in a heavy liquid called DMS for dense media separation.

"The light rocks float and the heavy rocks sink. You then have to look at the pebbles through a microscope and try to see if you've got minerals associated with diamonds."

Spence, who has been working on this project for about two years, said once the sand is divided into bags for size and looked at under the microscope, a good result would be to find one or two individual grains of indicator minerals in the bag.

"If you're right on top of a kimberlite there'll be hundreds but usually you're not that lucky."

Phil Jackson from Covello, Bryan and Associates was helping Spence with the screening and the screening machine was borrowed from Monopros Ltd.