From Plastic to Diamonds--Realizing an Alchemist’s Dream : Gems: A Hong Kong scientist is making tiny jewels from shopping bags and other reclaimed junk. Investors remain skeptical.

The adage that one man’s trash is another’s treasure is living truth for a Hong Kong scientist making diamonds from cheap plastic junk, even shopping bags.

In a simple, inexpensive university experiment reviving every alchemist’s dream of yielding riches from ordinary matter, Professor Hiroyuki Hiraoka is harvesting tiny precious diamonds from ubiquitous plastic, and beginning to capture world attention.

Hiraoka admits his diamonds are not quite a girl’s best friend, yet. But if he achieves his ambition, he could produce a line of diamond-coated costume jewelry, he said in an interview.

So far, the Hong Kong University of Science and Technology professor has not rattled the multimillion-dollar gem trade with his method.

“It’s just not a threat to the diamond industry,” said Thomas Wong, chairman of the Diamond Importers Assn. here. “Those crystals cannot be seen with the naked eye.”

Hiraoka and his students are not the first to try to re-create in the lab the gems that nature has spent an eternity forming. For centuries, back yard tinkerers and mining giants with a lot to lose have tried artificially to re-create one of the world’s strongest substances, so rarely found naturally.

But no one has succeeded making the gems as cheaply and easily, says the reserved, Japanese-born professor, who has lectured in the United States on his findings.

Hiraoka has patented the simple process in the belief it will one day become commercial. “This technique, nobody is doing it,” Hiraoka said as he surveyed his amateurish-looking equipment. “Of course we could make jewels.”

Plastic is the raw material used because it is full of carbon, the only ingredient of a pure diamond. And it is dirt cheap.

The secret is all in the technique.

Hiraoka uses his university’s bulky, old-fashioned laser machine and other apparently clumsy apparatus to produce the crystals. The laser sends shock waves through the plastic inside a vacuum chamber, creating a fireball that sprays out the tiny precious crystals. They fling themselves uniformly onto a specially prepared silicone-coated surface and stick like glue.

“As you can see, it’s a very simple set-up,” says the proud professor, surveying a gleaming diamond deposit several microns thick.

The rock-hard, shiny coating looks quite similar to stainless steel.

Though Hong Kong loves diamonds, buying $1 billion of polished stones in the first half of the year, Hiraoka has had trouble getting funding from a corporate sponsor to take the experiment to its next phase.

Other synthetic techniques are prohibitively expensive, requiring a cocktail of extremely high temperatures and expensive graphite, and the result is often patchy and does not stick. Analysts say it is therefore far more cost effective to mine nature for industrial diamonds, which make up well over half the haul in any diamond deposit.

But plastic is ever-present, and even with outdated equipment the scientist claims his results are better than those of his peers.

Hiraoka uses humble plastic shopping bags and even polystyrene, but plastic glass is his favorite. He buys it at the department store.

The scientist and his students admit they have not exactly produced the Hope diamond, just a few experimental, two-dimensional samples.