Convert from chalder, chaldron to stone

Unit Definition (chalder, chaldron)
The chalder, chaldron is a traditional British unit of volume or weight used for dry commodities such as coal or lime. As a volume measure, the chaldron is equal to 36 bushels, or 288 British Imperial gallons; this is equivalent to 46.237 cubic feet or 1.3091 cubic meters. As a measure for coal, the chalder equals 1/8 keel or 53 hundredweight (5936 pounds or 2692.52 kilograms). The words "chalder," "chaldron," and "cauldron" are English spellings of the same old French word, which originally meant a large kettle.

Unit Definition (stone)
The stone is a traditional British unit of weight, rarely used in the U.S. Originally the stone varied in size, both from place to place and according to the nature of the item being weighed. A stone of sugar was traditionally 8 pounds, while a stone of wool could be as much as 24 pounds. Eventually the stone was standardized at 14 pounds avoirdupois or approximately 6.350 29 kilograms - a convenient size because it makes the stone equal to exactly 1/2 quarter or 1/8 hundredweight. Today the stone is used mostly for stating the weight of persons or animals.