Complex sentence: Tin mining was centred in Cornwall and Devon, exploiting alluvial deposits and governed by the special Stannary Courts and Parliaments--tin formed a valuable export good, initially to Germany and then later in the 14th century to the Low Countries.
Split into simpler sentences: Tin mining was centred in Cornwall and Devon, exploiting alluvial deposits and governed by the special Stannary Courts and Parliaments. Tin formed a valuable export good, initially to Germany and then later in the 14th century to the Low Countries.