It appears we have now fully adopted the American billion (1000million) and proper British, too big to be useful, billion (1,000,000million) is pretty obsolete.
Lewissian Gneiss is one of the oldest rocks on the planet, which I think is about 4000 million (as i was taught) years old, Titchmarsh is kind of right.
It is like saying all brick built houses date from the last ice age though... and Snowdonian Slate roofs from the Caledonian Orogeny... etc.