Single I-type briquette, produced for industrial use in manually hand-fired boilers and furnaces. Sample from the earliest production at the State Electricity Commission's Yallourn Briquette Works, situated in the Latrobe Valley, near Morwell, Victoria, dated 1925. Manufactured from brown coal extracted in the adjacent Yallourn Open Cut Coal Mine. Construction of the Yallourn Briquette Works commenced in mid-1922, using primarily imported German technology and equipment.The plant began trial runs in mid-November 1924 and commerical sales of briquettes commenced in February 1925, with production reaching 350 tons/day by mid-1926.
I-type briquettes were originally the smaller of two forms of briquette made by the SECV, being pressed as a 10-inch (254 mm) long four-piece block or bar, with three narrow waist bands, which allowed the bar to be easily broken into four pieces or individual briquettes, each of a convenient size and weight to be shovelled up by hand. I-type briquettes were designed to be used as an industrial fuel, replacing black coal or firewood in hand-fired furnaces and boilers. At manufacture there were approximately 5,500 I-type briquettes to the ton, with each single briquette weighing about 6½ oz. (185 g).
Part of an original sample presented by the State Electricity Commission, 17 Jul 1931, comprising two joined quadruple-row blocks (now broken into four pieces) and four single briquettes of the same size. This piece one of the four individual briquettes or partr of the second (broken) bar. Other pieces from same sample now registered separately as HT 16836-16842, and HT 56110. Originally registered as part of ST 018406, which number is now reserved for the four broken pieces of the first quadruple I-type sample.
Dark browny/black in colour with hard glossy surface and relatively light in weight. One quarter of a quadrulple block, originally comprising four joined briquettes pressed as a single bar, measuring 10-inch x 2½-inch x 1¾-inch overall, with three narrow waist bands separating the four pieces. Sample has rounded corners and rough remnants of a broken waist joint at either end, giving it an approximately round shape when viewed from above or below, indicating that it was originally one of the two inner pieces from a four-piece block. A letter from the Electricity Commission, dated 30 Jun 1931, gave the following general analysis for briquettes manufactured at Yallourn (the quality of which wass standardised in the course of manufacture): Moisture - 14.00 % ; Volatile Matter - 42.40 % ; Fixed Carbon - 41.75 % ; Ash - 1.85 % ; -------------- Total 100.00 % -------------- Calorific value by bomb calorimeter was 9500 B.T.U. (gross) per lb. [See back of Registration Card for RN 018405].
Donation from Publicity Division, State Electricity Commission of Victoria (SECV), 17 Jul 1931
Place & Date Manufactured
Impressed with a raised letter capital 'I' on the upper face and an indented letter capital 'I' on the underside. Original adhesive label hand-written in blank ink reads: 'Yallourn 1925'
Type of item
76 mm (Length), 58 mm (Width), 40 mm (Height), 60 mm (Outside Diameter), 164 g (Weight)
Broken remains of neck 20 mm wide x 40 mm high.