John D. Dyer - Precious Gemstones Co.

Colored Stone Article

2007 The Front Row: The Gemmys

John Dyer of Precious Gemstones Co., Eau Claire, Wisconsin, has a reputation as a wunderkind. Almost 28, he has already won 20* AGTA Cutting Edge awards — and is the only gem cutter to sweep the Faceting category in two separate years.

His winning ZigZag™ Cut, a green Afghan tourmaline, is his first-ever Gemmy entry. It combines flat faceting and his trademarked V* groove.

Home-schooled, Dyer taught himself about gemstones. He was exposed to the business end while living in Brazil with his missionary family. He recalls an eye-opening emerald buying trip to Zambia* with his father and partner, David. Because Zambia* has a very small cutting industry, gems are cut elsewhere, imported back, and sold at exorbitant prices to tourists. So the Dyers decided to buy their own rough. “We were referred to a cutter. We went into debt. He overcharged us, and he did a lousy [job]. My father says, ‘We’ve done lots of things in our lives. We can do this better.’ ” The Dyers bought faceting machines and got into the cutting business.

The tourmaline for ZigZag™ Cut came from a dealer friend* in exchange for cutting some rough. Dyer was struck by the color and clarity of the green tourmaline, since so much tourmaline has an undertone of gray or black.

“Tourmaline is one of my favorite materials because sometimes you can get a nice-sized material,” he said; the finished stone weighs 10.36 cts. and is 23 mm long. Dyer’s goal was “to best utilize the shape of a relatively flat rough relative to the width.” The crown and sides were flat faceted with an Ultra Tech machine, but “I had to do something to make it sparkle, which is why the V* groove came into play.” The V* grooves were cut on the bottom with a variety of techniques to act like a series of miniature culets, “almost like many little pavilions.”

“In traditional faceting, if you go below a certain critical angle, the light passes right through. I managed to maintain a critical angle with each V* groove,” said Dyer.

- by Marlene A. Prost