The
carat of 205.5 milligrammes, it will be noticed, is used in the chief
centers of the diamond trade, and it is the weight in use in the United
States. One of these carats equals four grains avoirdupois or 3.174
grains troy, and 151.42 carats equal 1 ounce troy.
With
the extension of the diamond trade during the last twenty-five years,
these variations have proved confusing, and an effort has been made in
Europe to abolish the old system of carat weight with its divisions by
two into
and establish a
decimal
system on a base of 200 mgs. as the metric carat. The dealers in
diamonds, however, feared that such a radical change would disturb
trade, and the attempt failed. Governmental recognition of the carat as
