Convert from quartern-loaf to stone

Unit Definition (quartern-loaf)
The quartern-loaf is a traditional English unit of weight for bread. A quartern-loaf is made from a quartern of flour. The finished loaf usually weighs somewhere between 4 and 5 pounds (very roughly 2 kilograms).

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.