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 A HISTORY OF CORNWALL that his account nearly represents the indebted- ness of the county to the smelter Costar, of whom he speaks so highly. According to Borlase, 1 the ore was either spalled (broken with hammers), or bucked (bruised upon a rock with a bar of iron), and then re-sorted. The best part was washed and sifted into a tub through a griddle of inch-square meshes. Of this, the finer portion was jigged in water in another and smaller sieve, while the ' dredged ore ' was washed and picked, and the poorer part stamped, as was the case with tin, the crushed stones passing as usual from the stamp coffer to several pits, where it was distributed in accordance with its specific gravity. The heavier part remaining nearest the stamps was then jigged (a process brought in from the Derbyshire lead mines), 3 and the rest trunked, huddled, and tossed. 3 Pryce, in 1778, writes in much the same strain, but goes into wider detail. The dressing of copper ore, he says, cannot be according to one uniform method. 4 The hard and poor ores require much bruising and roasting before being clean, but the better grades are easier to operate. 6 The manner of dressing and cleansing is much like that for tin, but as good copper is usually dug and raised in large masses, as little as possible mixed with other matter, a great part of it is solid ore, and requires no washing. When it comes to the surface they sort out the big stones from the small and break them, throwing aside the poorer part, which is afterward to be straked and washed. But when the ore rises plentifully, and with little waste, it may be perhaps a loss to wash it, and therefore if it comes moderately dry a person near the shaft where it rises sifts it on a griddle or iron wire sieve. 6 The part that runs through, if not clean enough for sale, is washed, and it is seldom that griddled or small ore is so pure and clean as not to require this. The poorer and smaller part is usually carried to the strakes, sometimes after being griddled, but more often before, and as it comes from the mine. 8 This strake is made of two boards laid flat for a bottom, fourteen inches in the ground, on an inclined plane, with two sides formed of one deal board each, resembling a narrow, shallow chest without a cover. In it runs a rapid stream. One man throws the foul ore into the strake while another moves and tosses it with a shovel in the stream, and thus the slime, or finer ore, is carried by the water into a pit just below, and the stony, coarse, poor parts settling largely on the lower end of the boards are, at times, divided and cast aside to be stamped. 8 The better ore, 1 Borlase, Natural History of Cornwall, 203. " Pryce, Minera/ogia Cornubiensis, 243. 3 Borlase's account is substantiated by an eighteenth- century document of slightly later date. Add. MS. 6682, fol. 302-303. 4 Pryce, Minerahgia Cornubiensis, 236-238. 4 Ibid. 233. Ibid. 234. by its gravity, is deposited at the head of the strake. But if it contains much pure mundic this settles also at the head of the stream because of its weight, and is separated and laid by itself. Moreover, the largest stones, either of ore or of waste, which, by the motion of the shovel, rise uppermost, the dresser throws on one side and women and children pick the good stones from the bad. The rest is laid by to be bucked smaller with flat iron hammers, if the ore is worth it, otherwise it is taken to the stamps. The picked ore, which is rich, is given to girls called cobbers to break on big stones with ham- mers, after which it goes by the name of cobbed ore. It requires no water or further dressing, being fit to mix at once for sale. The stony ore being left by the pickers (dredge ore) is carried to the bucking-mill, which is something like a wooden coalscuttle placed on a low hedge, with a hard stone at its lower end, whereon a strong wench with a hammer breaks the ore to the size of small beans. Then it goes to the vat or kieve and is jigged. They fill the kieve half full of water, on the surface of which the jigger holds a coarse wire sieve into which another man throws the unclean ore. The jigger dips it into the water and shakes it there several times until the smaller part falls through to the bottom of the kieve. What remains in the sieve he reserves by itself until there is a quantity. This coarser size made by the sieve is jigged pure and clean if it be well given for ore. If not it is picked and the refuse bucked over again pursuant to its richness or poverty, and the dresser's direction and judgment. 7 When the kieve is almost full they pour off the water and take out the small ore, which, perhaps, they sort again after the same measure in sieves with smaller holes. Being thus divided they dress each sort apart in kieves half full of water with the proper sieves, whose holes are small enough to keep the ore from running through. The jigger has a peculiar movement which he gives the sieve, which causes the light waste to rise uppermost in it, and after that the ore, and then, at the bottom, the heavy mundic. To separate these, he takes a small semi-circular piece of wood, called the limp, with which he skims or rakes off the light refuse to be re-jigged, and then the ore, which he places by for sale, leaving the mundic to be jigged once more. 7 The light refuse of the ore is frequently straked again. The slimy fine ore which falls through the fine sieve to the bottom of the kieve is often cleansed by the tye (which is the same as the strake, but with a very slow and small stream of water), or by huddling or framing like tin ore, and, also, by jigging in a small close sieve. 7 Another method of dressing very fine and delicate copper and lead ores much speedier than buck- ing them is to give them over to dry stamps. 8 7 Ibid. 235. Ibid. 244. 566