Of the Use of the Brilliant Sizes in discover-ing ill-wrought ones.
Here it
may be proper to show, how far this ill manner of working before
mentioned may debase diamonds of larger sizes, and how much it may
contribute to the deception both of buyer and seller. To that end will
be shown the use of the sizes in discovering a well or an ill made
brilliant. For example, suppose two stones of six carats weight each,
the one a well-made, the other an ill-made stone; the first will tally
in all circumstances with No. 20, of six carats weight; and the last
may be loaded with undue substance, by which means its expansion may
not exceed one of five, or four carats weight. If any brilliant be so
circumstanced, it is to be valued only as it
