Carat (mass) Despite its being a non-metric unit, a number of metric countries have used this unit for its limited range of application. The Board of Trade carat was divisible into four "diamond grains", but measurements were typically made in multiples of carat. There were also two varieties of "refiners' carats" once used in the United Kingdom — the pound carat and the ounce carat. The pound troy was divisible into 24 "pound carats" of 240 grains troy each; the pound carat was divisible into four "pound grains" of 60 grains troy each; and the pound grain was divisible into four "pound
Ceratonia siliqua a result, the carat also became a measure of purity for gold. Thus, 24-carat gold means 100% pure, 12-carat gold means the alloy contains 50% gold. The carob tree grows up to tall. The crown is broad and semispherical, supported by a thick trunk with rough brown bark and sturdy branches. Its leaves are long, alternate, pinnate, and may or may not have a terminal leaflet. It is frost-tolerant to roughly . Most carob trees are dioecious and some are hermaphroditic, so strictly male trees do not produce fruit. When the trees blossom in autumn, the flowers are small and