Stones other than Diamonds
Accompanying diamonds in the concentrates are a number of other minerals of high specific gravity, and some of notable beauty. Among these are the rich red pyrope (garnet), sp. gr. 37, containing from
Dictionary of Metric and other Useful Measures the diamond carat is given as equal to 3'1683 grains = op2053 gramme=4 diamond grains; 1 diamond grain = 0792 troy grain ; 151-5 diamond carats = 1 ounce troy.
Webster's International Dictionary gives the diamond carat as equal to 3I troy grains.
The Oxford English Dictionary says the carat was originally -x\% of an ounce, or 3J grains, but now equal to about $\ grains, though varying slightly with time and place.
The Century Dictionary says the diamond carat is equal to about 3^ troy grains, and adds that in 1877 the weight of the carat was fixed by a syndicate of London, Paris, and Amsterdam jewellers at 205 milligrammes. This would make the carat equal to 3'163 troy grains. A law has been passed in France ordaining that in the purchase or sale of diamonds and other precious stones the term "metric carat" shall be employed to designate a weight of 200 milligrammes (3'o86 grains troy), and prohibiting the use of the word carat to designate any other weight. 70
