Convert lbs to stone
Pound
The pound or pound-mass is a of mass used in the imperial, United States customary and other systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly 0.453 592 37 kilograms, and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is lb; an alternative symbol is lb m (for most pound definitions), # (chiefly in the U.S.), and ℔ or ″̶ (specifically for the apothecaries' pound).
Stone
A stone (symbol: st) is an English and imperial unit of mass. It is defined as 14 pounds or 6.35029318 kilograms.
The name "stone" derives from the use of stones for weights, a practice that dates back into antiquity. The Biblical law against the carrying of "diverse weights, a large and a small" is more literally translated as "you shall not carry a stone and a stone (בן ואבן), a large and a small". There was no standardised "stone" in the ancient Jewish world, but in Roman times stone weights were crafted to multiples of the Roman pound. Such weights varied in quality: the Yale Medical Library holds 10 and 50-pound examples of polished serpentine, while a 40-pound example at the Eschborn Museum is made of sandstone.