GLOSSARY OF TERMS
I
Illusion
A setting whereby metal surrounds the stone, in a design and such a way that makes the stone look bigger than it actually is.
Inclusion
An internal clarity characteristic of a gemstone. See The Four C’s for further information.
Iridium
A chemical element with the symbol Ir. Iridium is a brittle metal and part of the platinum family. Iridium is often alloyed with platinum to make the metal harder – a practice often used in American jewellery in the early 1900s.
