London: German researchers have developed a unique X-ray technique that brightens the prospects of locating diamonds hidden deep in rocks.

This new technology would allow diamond hunters to pinpoint larger diamonds deep down the earth, avoiding the conventional method of breaking up the entire rock, as it requires a lot of energy.

"The X-ray's eagle eye could even find the highly coveted rare earths that are concealed in old cellphones, computers, and television sets to utilise them," said the Fraunhofer Institute's development centre for X-ray technology.

The new technique produces two images of the same object using different X-ray spectra.

A specially-developed algorithm filters the data from both the images, distinguishing diamond from Kimberlite rock, an igneous rock known for containing the gem, said the centre.

This technique can detect diamonds in ore that are several hundredths of an inch on up to grains that are nearly two inches in size, media reports said.