Chinese scientists who have created lab-grown, one-carat artificial diamonds in a week said the process is like planting crops with "seeds" and "fertilizers".

The seed is a small piece of natural diamond and the fertilizer is methane gas, according to the scientists from the Ningbo Institute of Materials Technology and Engineering under the Chinese Academy of Sciences.

Li He, a researcher on marine new materials and application technology, said that they first made a tablet with a natural diamond piece, and used a methane molecule to separate out the carbon atom to deposit on the seed piece in the laboratory.

An artificial diamond can grow at a pace of 0.007 millimeters per hour, and in seven days, it will be about one carat in size. Its hardness and purity are comparable to those of natural diamonds.

Due to different processing techniques, one-carat natural diamonds are priced at about 20,000 yuan to 200,000 yuan ($2,830 to $28,306), but artificial diamonds that size are about 3,300 yuan, about one-sixth price of natural ones.

These artificial diamonds can be used for jewelry and the technology could help manufacture precision instruments in optics, lasers, radar and other fields. (chinadaily.com.cn)