Figuring the angles
Diamond cutter on leading edge of North's newest industry
NNSL (Oct 08/99) - Master diamond cutter Peter Finnemore is from the old school, where students had to prove their skills on ball bearings before they were permitted to touch a diamond.
"That's how we started, cutting facets into a ball bearing," said Finnemore, manager of the Sirius Diamonds Ltd. polishing factory at the Yellowknife Airport. "It took five years of apprenticeship before I became a qualified journeyman."
Diamond cutting has come a long way in the last 15 years, he said. Specialization and sophisticated machinery are now commonplace in most plants.
In the Sirius plant there is a series of robotic cutters, laser saws and another laser that engraves the microscopic polar bear trademark that marks each of the finished diamonds the factory produces.
Much of Finnemore's time these days is spent marking cuts on rough stones to exact maximum value. He also checks the work of the 20 polishers employed there. In diamond manufacturing, polishing and cutting both refer to the same thing -- transforming a rough diamond into a finished one.
That's the pivotal challenge facing all diamond manufacturers, he said.
"I don't look at them as shiny stones," he said. "It's always nice to see it when it's polished, but the rough is what I live for, the challenge of getting the highest value from the diamond."
About 65 per cent of a rough diamond is lost in the polishing. The challenge is determining what shapes and cuts will maximize the beauty and price of a stone.
During his 17 years as a diamond cutter and polisher Finnemore established a reputation as one of the world's best. He has helped cut some monumental diamonds, among them the 260 carat Guinea Star.
Cutting such diamonds takes months of study. Models are built of the piece of rough to determine precisely how to get the most out of the stone.
There is always a financial risk associated with cutting a diamond, said Finnemore, and all of it falls on the shoulders of the manufacturer.
"Diamonds are the most expensive material in the world today," he said. "Accidents do happen. They are extremely brittle."
With his wife and two daughters, Finnemore moved here from world diamond capital Antwerp, Belgium two months ago to help organize the Sirius polishing plant.
Though it is his first winter in the NWT, Finnemore said he got some good training last year. From September to November he was working in Siberia. It was -40 C when he left.