| Gem
Cutting
The
most primitive form of lapidary, or gem cutting,
was the fashion¬ing of beads. Later the beads
were ground into a more regular shape, such as
a circle or an oval, and one side was ground flat.
A
cut gem with a rounded top and flat, convex or
concave bottom is called a cabochon, from an Old
French word meaning "head." By the 17th
Century, sophisticated gem-cutting techniques
were developed, culminating in the art of faceting.
. 
This
is the placement of regular; flat surfaces in
apre-selected geometric pattern. Today, faceting
is widely employed for cutting even inexpensive
gems, and machines have been developed that can
do much of the job automatically. But in many
parts of the world, fine gem rough is still cut
by hand, using relatively simple and 'unsophisticated
tools, such as the so-called "jamb peg."
In the hands of an expert, the jamb peg can produce
results equal to any machine. |
