14. Fireglo briquettes, manufactured by Les Combustibles de Normandie at Caen, France, and by La Société Rouennaise de Defumage at Rouen, France, which–
(a)comprise washed Welsh duffs (as to approximately 92 per cent of the total weight) and coal pitch binder (as to the remaining weight);
(b)were manufactured from those constituents by a process involving roll-pressing and heat treatment at about 330°C;
(c)are ovoids with three lines on one side and are smooth on the other side;
(d)have an average weight of 30 grammes per briquette; and
(e)have a sulphur content not exceeding 0.8 per cent of the total weight.