SCHEDULEAuthorised fuels
53.
Therma briquettes, manufactured by Maxibrite Limited at Llantrisant, Rhondda Cynon Taff, which—
(a)
comprise anthracite fines (as to approximately 84% of the total weight), petroleum coke (as to approximately 12% of the total weight), and starch as binder (as to the remaining weight);
(b)
were manufactured from those constituents by a process involving roll-pressing and heat treatment at 250°C;
(c)
are oval/tear shaped briquettes with a line through the centre;
(d)
have an average weight of 26g per briquette; and
(e)
have a sulphur content not exceeding 2% of the total weight.