The factory made porcelain of very high quality, especially in the years from 1813–1814 and 1817–1820. Porcelain produced by Nantgarw was extremely white and translucent, and was given overglaze decoration of high quality, mostly in London or elsewhere rather than at the factory. The wares were expensive, and mostly distributed through the London dealers. Plates were much the most common shapes made, and the decoration was typically of garlands of flowers in a profusion of colours, the speciality of the founder, William Billingsley. With Swansea porcelain, Nantgarw was one of the last factories to make soft-paste porcelain, when English factories had switched to bone china, and continental and Asian ones continued to make hard-paste porcelain.