carat

1. N-COUNT Carat is used after a number to indicate how pure gold is. The purest gold is 24-carat gold. 開; 黃金純度

...a twenty-four-carat gold necklace. ...一條二十四開金的項鏈。

2. N-COUNT A carat is a unit for measuring the weight of diamonds and other precious stones. It is equal to 0.2 grams. 尅拉 (鑽石等寶石的計重單位，相儅於0.2尅)

The gemstone is 28.6 millimetres high and weighs 139.43 carats. 這顆寶石高28.6毫米，重達139.43尅拉。