Diamonds and the more valuable precious stones generally are bought and sold by the weight called a carat. This carat, whatever its precise value, is always considered as divisible into four diamond or pearl grains, but the subdivisions of the carat are usually expressed by the vulgar fractions, one fourth, one eighth, one twelfth, one sixteenth, one twenty-fourth, one thirty-second, and one sixty-fourth. The origin of the carat is to be sought in certain small, hard, leguminous seeds, which, when dried, remain constant in weight. The brilliant, glossy, scarlet-and-black seed of _Abrus precatorius_ constitutes the Indian rati, about three grains; the _Adenanthera pavonina_ seed weighs about four grains. The seed of the locust-tree, _Ceratonia siliqua_, weighs on the average three and one sixth grains, and constitutes, no doubt, the true origin of the carat. Another[377] of the more notable of these weight-units used for precious stones and precious metals is the _candarin_, _condorine_, or _cantarai_, also termed by the Chinese _fun_ or _fan_, and by the south Indians a _fanam_, and used all over the Indo-Chinese archipelago. This is by origin a large lentil or pea of a pinkish color dotted with black, about double the size of the _gonj_, and possessing the same quality of very slight variability of weight when dried. It is probably a variety of the same botanic genus or species as the _Abrus precatorius_. The value when reduced to absolute standard became a subsidiary part or submultiple of the weight of some local coin, rupee, or pagoda, or a decimal fraction of some local tchen, as in China and Japan. The following derivation of the word carat is given by Grimm: “Carat. Italian: _carato_; French: _carat_; Spanish and Portuguese: _quilate_; Old Portuguese: _quirate_, from Arabic _qirat_, and this from the Greek, κεράτιον.”[378] The carat is not absolutely of the same value in all countries. Its weight, as used for weighing the diamond, pearl, and other gemstones in different parts of the world, is given in decimals of a gram, by the majority of the authorities, as follows: Grams In Grains Troy Indian (Madras) .2073533 3.199948 Austrian (Vienna) .20613+ 3.18107+ German (Frankfort) .20577+ 3.175514 Brazil and Portugal .20575+ 3.175206 France .2055+ 3.171347 England .205409 3.169943 Spain .205393 3.169696 Holland .205044 3.16431+