Following the north bank of the Firth of Tay estuary from Dundee you eventually arrive at the rich and fertile farmland of the flat and low-lying Carse of Gowrie. About 5 miles from the city, at the edge of the Carse, is the hamlet of Ballindean, located on sedimentary Devonian age Upper Old Red Sandstone deposits partly overlain to the north by extrusive agate-bearing andesite and basalt lavas. These comprise the southern end of the modest elevation Sidlaw Hills between 5 and 6 miles in breadth at this point stretching towards and beyond the city of Perth to the west.

Ballindean lies on the southern edge of the Sidlaws and near the centre of a number of agate localities including Agate Knowe, Ballindean Farm, Tinkletop and Inchture. Agates from this locality rarely exceed 50mm in diameter and usually occur as gentle pastel shades in surprisingly large numbers of uncracked and high quality stones. Agate Knowe in particular, comprising a small tree lined knoll produces some exquisite specimens described by Matthew F Heddle as surpassingly beautiful.

Sadly for modern day collectors most of the local fields have been under pasture for many years due to historical changes in agricultural practice. Should they ever be returned to arable use they would once again become productive sites.