This large gneiss boulder is found on Sanday. It originally rested 200 m west of Saville but was then moved to near the farm of Scar. The Saville Boulder has a distinctive mineralogy dominated by oligoclase and penetrated by threads of actinolite and accompanied by hornblende.

For well over a century fragments of chalk and flint have been recovered from the shelly tills of Orkney and Caithness. Rae (1976) plotted the known distribution in Orkney, demonstrating a marked concentration on the eastern side of the islands.

In a few parts of Scotland, including northern Lewis, Berwickshire, Buchan, Caithness and Orkney, the last ice sheet flowed across marine sediments before moving on to the current land area.