SANTA ROSA, Calif. (AP) — Alison von Sternberg thinks of herself as cutting diamonds from the inside out. It takes a Zen state of mind.

In her Sonoma County workshop, the bright-eyed 43-year-old sat serenely behind her scaife, a diamond-cutting wheel that looks like a record turntable, albeit one that spins at 3,800 rpm. Coated with diamond dust and olive oil, it abrades the side of a diamond to create a facet.

"You have to be with the diamond all the time," von Sternberg said. "I think of it as sculpting because I'm making a work of art. Every diamond is different, so it doesn't get boring."

Alison and her husband, Richard von Sternberg, 58, say they have perfected a method of cutting that makes a diamond leap incandescently to life, shot through with brilliance (white light) and fire (colored light). Under a special viewing mechanism called a Firescope, it shows a distinctive eight-spoke pattern.

The couple named their cut and their company EightStar. They say their techniques could revolutionize diamonds — but it's not clear whether the diamond industry will receive them with open arms or a cold shoulder.

Last year, a Swiss diamond enthusiast who has a 25 percent stake in the company bought a spectacular, $2.3 million diamond to be recut to EightStar proportions. An EightStar cutter reduced it from 14.89 carats to 13.42, lopping off a quarter-million dollars' worth of weight.

"Every little bit of weight that comes off makes people sick to their stomach," Richard said. "People who heard we were going to do this thought we were nuts." But the new cut made the light dance and the colors vibrate inside, he said.

EightStar turns out about 2,000 diamonds a year, a 10th of the volume of bigger companies.

Richard von Sternberg said annual sales are in the millions of dollars. He declined to specify the profit margin, although he said it's low because the cutting process is so labor intensive.

The von Sternbergs were dealers of colored gemstones until a theft wiped out their inventory. They stumbled into EightStar when an acquaintance opened a diamond-cutting factory in Sonoma County using techniques that a Japanese expert had spent years perfecting. They bought the company in 1991 for less than $1 million when their acquaintance decided it was too overwhelming an enterprise for him.

EightStar cutters spend an average of 32 hours to cut a single diamond. Cutting factories in Israel and India crank diamonds out like widgets at the rate of one every 45 minutes.

EightStar diamonds cost about 40 percent more than those mass-produced gems, but some jewelers say they're worth it.

At E.R. Sawyers Jewelers in Santa Rosa, owner Doug Van Dyke laid out three diamonds against black velvet. One seemed clearly larger and more dazzling.

"That's the EightStar," he said. "It's three-quarters of a carat. The other two are each one carat. The cut makes the EightStar look bigger."

The American Gem Society and the Gemological Institute of America, the two major labs that grade diamonds, have begun to recognize cut as a critical factor.

Peter Yantzer, director of the grading laboratory for the American Gem Society, agreed that cut affects perception of size.

"A well-cut diamond can outsparkle and appear larger than a poorly cut diamond of more carat weight," he wrote in an e-mail. "Additionally, because of their brilliance, well-cut diamonds also can mask a diamond's imperfections in color and clarity."

As for EightStar, Yantzer wrote: "They cut to a very high degree of precision, and their diamonds fit the parameters of AGS's top grade. Like many other firms worldwide, this is an ideal situation for cut."

Until recently, cut was the least noticed of the four C's of grading diamonds — cut, color, clarity and carats — even though it is the only factor that humans can influence.

Now, diamond companies have begun to market cut as a way to differentiate their products. Signature cuts such as Tiffany & Co.'s Lucida command premium prices. At the same time the upper end gets more rarified, diamonds are going further down market; Wal-Mart is now the country's biggest seller of the gems.

To the layperson, "cutting" a diamond seems like a misnomer. Strictly speaking, what appears to be going on is grinding, one facet at a time, interspersed with meticulous checking through a jewelers loupe and with an optical viewer to ensure that the angles are perfectly aligned.

Despite being the hardest known substance in the universe, diamonds can shatter in the hands of an inexperienced cutter.

Some diamond experts question whether branded cuts are worth the extra money or are just a marketing gimmick.

"I think EightStar puts out a wonderful product that is overpriced and overpromoted," said Robert James, a gemologist in San Antonio, Texas.

"If you have to carry an ideal (viewing) scope around with you to explain to friends why you paid so much more for your diamond than theirs . . . you have paid too much for your diamond," he wrote in an online discussion. He wrote that the party test — how a gem looks out in the real world — is the best gauge.

The von Sternbergs say that the diamond establishment has shied away from endorsing their techniques because it could have huge ramifications for big companies in the multibillion-dollar industry. If the EightStar cut really is the best, other diamond merchants are holding bags of rocks that suddenly may be worth a lot less.

"We're the pariah of the industry," Alison said. "We're trying to promote something new that threatens everybody. It's been an uphill climb to get any recognition."

Gregory Sherman, an independent jewelry consultant who teaches gemology at the California Institute of Jewelry Training in Carmichael, says EightStar's ultimate role is as a boutique cutting firm that produces superior stones.

"Each diamond is as different as a snowflake or a fingerprint," he said. "If you take a standard approach to cutting a diamond (as do most diamond cutters) and expect each to perform the same based on external measurements, they won't all come out the same."

EightStar, by contrast, "adjusts the proportions to fit each individual diamond and make each as beautiful as it can be," he said.

"They look at the relationship between each facet, the symmetry, the way they're angled. They're the only company I know of that does that, and their diamonds are cut to perfection."