WHAT IS A CARAT ?

Ashburton Guardian, Volume V, Issue 1458, 17 January 1887, Page 2

WHAT IS A CARAT ?

ThiP, saya "Cassell's CyclopoeJia," fs the name given to the Beech of the Abjßfilnian coral flower, or coral tree, which, being very small, and very equal In siza, were formerly used m weighing preoioua atones. Hence carnt has became the name of the weight used by jewellers for weighing precious stones, and the word is also used to indicate the proportion of pure gold present m any alloy of that metal.. As a weight for dhmonds, the carat represents 3-1-6 Troy grains, and is divided into fourths (or oar at grama) as well as into eighths, aixteenths, thirty-second and sixty-fourths. In regard to gold, the wcrd osrat represents no absolute weight, but only a ratio or proportion. Gold fa never usad for coinage, jewellery, etc, m a pure fttate; it ia alloyed with a coarser metal, sometimes with copper aod silver, and sometimes with copper alone, for the purpose of working, and to secure tbe necessary hardness. To indicate the proportion of pure gold m Any motnl thui alloyed, tbe metal is divided into 24 parts, or carats — '• 24 carat raeantag pure gold, and any less number cf carats meaning tbe fraction or proportion of gold to be found m the alloy. Sterling gold (he gold <f our coinage) contain? 22 parts of goM and two p&Hs of alloy; it ia tborofore said to be "22 carat fine," or "22 carat gold." The lower standard, usod for watch *"-'. .d? fi jjwellery, etc, contains 18 parts of gold and six pr.ris of alloy; it ia therefore called " 1.8-cajMt gold." But a much larger proportion of alloy is often introduoed into gold represented qb " st&n '- ard"; thus we have 15, 12, and oven 9 carat gold, In many manufactured articles the number of carats of pure gold is indicated by a figu-e whioh forms a part of the " hall mark " p. tamped on them by the Society of Goldsmiths.