‘Hugely exciting and rare’: Neolithic polishing stone found in Dorset

Polissoir', discovered in Valley of Stones nature reserve, was used about 5,000 years ago to hone tools such as axes

At first glance it looked like nothing more than a rugged boulder jumbled among many others on the floor of a valley in the West Country.

But a smooth, glossy dip in the stone indicated that it was something very special - a vanishingly rare polissoir", or polishing stone, used 5,000 years ago by Neolithic people to hone tools such as axes.