All three pots contain quartz (often milky), feldspar and small lumps of grey granite (Biotite Granite) which looks very similar to the Gatehouse-of-Fleet granite and Creetown Granite. This suggests that the source of this material lies to the west of Kirkcudbright rather than to the east. Hence the grits from all three pots, and therefore the manufacture, are likely to have been quite local to the site.