There are two UK thrushes, the song thrush and the mistle thrush. They look simolar but the mistle thrush is larger. The song thrush is the one that sings from the tops of trees whilst the mistle thrush makes a characteristic 'rattle' (don't know how to describe it). The song thrush is the one that uses a stone as an anvil to break open snails.
If it is a song thrush the nest will be made of grass or similar. It will be lined with mud/cow muck or similar which dries hard to give a very smooth surface, no soft material. The eggs will be blue with black spots.
The mistle thush makes a much bulkier and untidy nest of grass etc. It is lined with softer material and the eggs are blue/green with brown spots/blotches.