Rosa's heart was racing from the four cups of coffee she had just finished, but she thought she might be having a heart attack.
A carat is a unit of weight for diamonds and other gemstones. One carat equals 200 milligrams (0.200 grams). There are 453 grams in a pound (1,000 grams to a kilogram). Therefore, if your fiancee weighs 170 pounds, you have a 385,050-carat fiancee! A karat, when used with gold, is a unit of purity-- 24-karat gold is pure gold, but usually you mix gold with a metal like copper or silver to make jewelry (because pure gold is too soft). Each karat indicates 1/24th of the whole.
Pure 24k gold is normally too soft for use in jewelry, so jewelers mix gold with another metal like nickel or silver to harden it, creating gold alloys of various purities: 10 karat gold is 41.7% pure gold; 12 karat gold is 50% pure gold; 14 karat gold is 58.3% pure gold and is ideal for jewelry because of its durability and affordability; 18 karat gold is 75% pure gold and is preferred in jewelry for its beauty and durability; and again, 24 karat is 100% pure gold and is therefore too soft ...