Is this Decipher (2001) by Stel Pavlou...?
From Wikipedia:
In Antarctica, an oil drilling venture is taking place by fictitious oil company Rola Corp. It is an unstable time in the region because the US and China are at loggerheads over mineral and oil rights, and the geopolitical landscape is dicey. The drill ship does not strike oil, but does discover a very hard form of diamond which turns out to be Carbon 60. Not only that, but the samples they retrieve have hieroglyphic writing on them.
Meanwhile, the US military has been monitoring unusually high solar flare activity and are worried about its effect on their fleet of satellites. While observing Chinese military maneuvers in Antarctica, the spy satellite picks up a highly unusual energy signal emanating from two miles beneath Antarctica's ice sheet.
When the US military and Rola Corp. pool their resources it is discovered that not only is the diamond-type material reactive to the sun, but the time of the energy pulses under the ice in Antarctica, match the timing of flare activity from the Sun.
A team of scientists are assembled to unravel the mystery. From Richard Scott, a linguistic Anthropologist, to Jon Hackett a Complexity Physicist. The team soon discover that the same energy signature from Antarctica is being detected by satellites from ancient monuments all over the Earth. From the Amazon jungle to Egypt and China. Inspired by stories of the ancient flood of Noah, Scott embarks on the mammoth task of deciphering the mysterious language found on the material, and comparing what it has to say with the ancient myths and legends of floods from all around the world.
The myths all have similar themes. They talk about the Sun, the destructive power coming from the sky, a flood, and a mythical lost city, known more famously as Atlantis. More than that, the myths talk of the cyclical nature of this destruction and point to an event that happened 12,000 years ago that may well be happening all over again.
From the Google Books preview of the book itself.
She looked at the stone. It was Carbon 60. And from what she could determine, it was integrated with another type of diamond that was even tougher, conceived of in the mid-1990s by some Harvard professors and dubbed Diamonite. It was a compound of carbon and nitrogen atoms. β-C3N4. The bucky-ball chunk of diamond was made up of molecules that consisted of sixty carbon atoms in a spherical geodesic formation. Known as C60, it was tough. And Diamonite was theoretically even tougher. Together, they made a formidable compound — ten, maybe a hundred times stronger than ordinary diamond. This definitely couldn't be naturally occurring. Since the mid-1950s, when General Electric had a stab at it, people had been trying to synthesize diamond. The best anyone had come up with was an inferior film that could be coated onto the tip of tools. This was evidence of a far more advanced technology.
