The United Kingdom is the people who use stone for weight.
The word stone when used for weight measurement in the United Kingdom, literally comes from the usage of large stones as a standard for weighing various commodities.
Originally, the size of the stone often varied from place based on the size of a stone someone chose to be the standard for the town/area.
The stone or stone weight (abbreviation: st.) is an English and imperial unit of mass equal to 14 pounds (approximately 6.35 kg).
The stone continues in customary use in the United Kingdom for body weight.
Americans never use the stone as a weight, which is in universal use in England (especially to weigh people).
The hundredweight (cwt) in England is always 112 pounds, or 8 stone.
In the US, the hundredweight is 100 lb, unless noted as otherwise.
The U.S. is one of the few countries globally which still uses the Imperial system of measurement, where things are measured in feet, inches, pounds, ounces, etc.
1 stone (st) is equal to 14 pounds (lb).
Only three countries the U.S., Liberia and Myanmar still (mostly or officially) stick to the imperial system, which uses distances, weight, height or area measurements that can ultimately be traced back to body parts or everyday items.