Further work has been carried out on the densification of Stockton coke to confirm Allan’s work (3), which showed that an acceptable density could be obtained by fine grinding and briquetting. The effect of particle size on this densification has now been studied. The density of -7 to +14 B.S. mesh fraction, from briquettes made from -350 mesh coke and heated to 1400°C for 1½ hours, exceeded 42lb/ft³. This was the smallest particle size tested and gave the highest density. The real specific gravity of the heated coke was found to be independent of particle size, but depended markedly on whether the sample was from heated powder or heated briquette.