# The Smoke Control Areas (Authorised Fuels) (Wales) Regulations 2019, Paragraph 11

Extent: E+W

Black Diamond Gem briquettes, manufactured by Coal Products Limited at Immingham Briquetting Works, Immingham, North East Lincolnshire, which—
(a) comprise anthracite duff (as to approximately 20 to 30% of the total weight), petroleum coke (as to approximately 40 to 45% of the total weight), bituminous coal (as to approximately 12 to 22% of the total weight) and molasses and phosphoric acid binder (as to the remaining weight);
(b) were manufactured from those constituents by a process involving roll-pressing and heat treatment at about 300°C;
(c) are pillow-shaped briquettes marked with two parallel indented lines running latitudinally around the briquette;
(d) have an average weight of 160 grams; and
(e) have a sulphur content not exceeding 1.5% of the total weight.

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Source: https://www.legislation.gov.uk/wsi/2019/50/schedule/paragraph/11 (the official version)
Page: https://openlegislation.uk/smoke-control-areas-authorised-fuels-wales-regulations-2019/schedule/paragraph-11
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.