Mount Pentelicus marble

Isotope chemistry can tell you which quarry a piece of marble was cut from. The Elgin Marbles came from Unit 3.

Mount Pentelicus stands in Attica, northeast of Athens and southwest of Marathon, and it has been famous for its stone since antiquity. Britannica describes the range as enclosing the Attic plain on its northeast, with a chief summit called Kokkinaras about ten miles northeast of Athens at 3,632 feet; the high point is also given as Pyrgari at 1,109 metres. Either way it is visible from most of the Attica basin, and it is still 60 to 70 per cent forest.

Pentelic marble built classical Athens. It is white with a uniform faint yellow tint that makes it shine gold in sunlight, calcitic with quartz as an accessory mineral, fine grained with occasional fossil clasts. Much of the Acropolis is made of it, and it was later exported to Rome for building and sculpture. In classical times there were 25 quarries on the south slope alone, between roughly 2,500 and 3,300 feet, and they supplied the stone for most of the buildings and sculptures of Athens in the 5th and 4th centuries BCE.

The provenance science is the good part. The marble divides into three units that can be told apart by their carbon-13 and oxygen-18 values, and those values have been used to match marbles from the Acropolis back to the particular quarry they came out of. That is how the Elgin Marbles were traced to Unit 3.

You cannot quarry here now. A ban was imposed on the south slope in the 1960s to stop the landscape being scarred, and the ancient quarry is protected by law and worked only to supply the Acropolis Restoration Project. The road the blocks travelled in antiquity survives, a continual downhill following the natural lay of the land, researched and fully documented by Manolis Korres, the chief architect of the Acropolis restoration, in his award-winning book From Pentelicon to the Parthenon.

There was a sanctuary to Athena at the summit, and a monastery sits in the middle of the mountain. In early July 1995 a fire burned for about five days and took three quarters of the slopes.