(a) It shall be unlawful to sell, or offer to sell, any coal, coke, or charcoal in any other manner than by weight. When sold by the ton, 2,000 pounds avoirdupois shall be the weight of the ton.
(b) No coal, charcoal or coke shall be sold at retail which contained, at the time the weight was taken, more water or other liquid substance than is due to natural conditions, weather conditions or causes incident to the mining, cleaning, or handling of the coal, charcoal, or coke, except by and with the consent of the purchaser.