A fragment of Coade Stone was analyzed by optical microscopy, scanning electron microscopy, x-ray diffraction, atomic absorption spectroscopy, and electron microprobe. These analyses indicate that raw material was a ball clay from Dorset or Devon, to which was added 5-10% flint, 5-10% fine quartz sand, at least 10% grog (possibly crushed stoneware), and about 10% soda-lime-silica glass, which acted as a vitrifying agent. -- AATA