Convert from carat [international] to slug

Unit Definition (carat [international])
The carat [international] is a unit of mass used for diamonds and other precious stones. Originally spelled karat, the word comes from the Greek keration, a carob bean; carob beans were used as standards of weight and length in ancient Greece in much the same way barleycorns were used in old England. Traditionally the carat was equal to 4 grains. The definition of the grain differed from one country to another, but typically it was about 50 milligrams and thus the carat was about 200 milligrams.

Unit Definition (slug)
The slug is a unit of mass in the English foot-pound-second system. One slug is the mass accelerated at 1 foot per second per second by a force of 1 pound. Since the acceleration of gravity (g) in English units is 32.174 04 feet per second per second, the slug is equal to 32.174 04 pounds (14.593 90 kilograms). The slug was formerly used in calculations in mechanics and engineering, but it has been largely abandoned in favor of metric units. The unit was called the "engineer's mass unit" during the late nineteenth century. The British physicist A. M. Worthington first called it a slug in a 1902 textbook. (Probably he had in mind older uses of the word to mean a weight or a projectile. In the 1600's a slug was a roughly shaped lump of metal shot from a primitive cannon.)