He had several small, but very perfect diamonds with him, and he gave them to me, to have tested in any way I desired.

"It is a perfect diamond, the size of a man's head; spherical and hollowed out."

Some people said it was a single perfect diamond a kilometre long that had been grown from charcoal.

The largest, most perfect diamond that ever was.

In the 21st century, the technology to produce perfect diamonds synthetically was developed.

She had never seen anything like it: an emerald inside a perfect diamond.

"We need large, perfect diamonds to make high-pressure devices for our research," he said.

In the early 1980's, the price for a perfect 1-carat diamond peaked at about $65,000, only to plunge to $10,000 a couple of years later.

At the time it was considered the largest most perfect diamond in Europe.

Somehow, for some people, the simple balloons of one's childhood become one perfect diamond in adulthood.