Glossary of Terms
14K Gold
Slightly more than one-half pure gold, or 14/24ths.
18K Gold
18/24ths or three-quarters pure gold.
Beauty
The beauty of a jewel is determined by its colour, brilliance, "fire" and
lustre.
Bezel
A bezel setting is when a rim holds the jewel and completely surrounds it.
Brilliance
The brilliance of a jewel is created by cutting designs that use the
jewel's refractive index and is measured by the amount of light that enters
the jewel and is reflected back to the viewer.
Carat
A unit of weight for jewels. One carat is equivalent to 100
points or one-fifth of a gram.
Cleavage
The natural way a mineral breaks, along certain planes
based on its internal crystalline structure.
Corundum
Corunmdum is a very hard mineral. It is called ruby or
sapphire, depending on the colour. In its rare pure form, corundum is
colourless and called white sapphire.
Crown
The upper portion of a cut jewel, above the girdle.
Culet
The tiny facet on the pointed bottom of the pavilion, which is the portion
of a cut jewel below the girdle.
Cushion
A mixed-cut jewel shaped like a square pillow.
Cut
The geometric proportions of a jewel, and the way it is shaped.
Durability
The durability of a jewel is determined by its hardness, or resistance to
scratching, and its toughness, or resistance to chipping or cleaving. The
jewel's hardness also determines the extent to which brilliance and "fire"
can be highlighted by cutting with sharp, highly polished facets.
Facet
Any of the flat sides of the jewel. This style of cutting
gives the jewel many small faces at diverse angles to one another. The
placement, shape and angle of the facet are carefully planned to display
the jewel's natural beauty, fire, colour, and brilliance to the fullest
potential.
Filigree
Gold or silver wire that have been twisted into patterns
and soldered into place.
Fire
The dispersion of a jewel combined with the cutting design results in the
"fire," or the breaking of light rays into the spectrum of colors and is
measured by the amount of colored flashes viewed when the jewel is moved in
various lighting conditions.
Girdle
The outer edge of a cut jewel that separates the crown from the pavilion.
Karat
The measure of the purity of gold. 24K is pure gold, however its
considered too soft for use in jewelry, and is alloyed with other metals to
strengthen it.
Lustre
Lustre is the amount of light that is reflected back to the observer from
the surface of the jewel.
Millegrain
A setting in which the band or stone is secured by tiny
beads (grains) of metal.
Padparadscha Sapphire
A rare pink-orange variety of corundum. These gems are
mined in Sri Lanka and usually heat treated to improve and intensify
colour.
Pavillion
The lower portion of the jewel, below the girdle.
Point
100-hundredth of a carat.
Prongs
Several tips or clamps used to hold the jewel in place.
Rarity
Rarity is the availability or perceived availability of a
jewel.
Rough
Uncut jewels.
Shank
The part of the ring that encircles the finger.
Solitaire
An individual jewel set by itself in a piece of jewellery.
Twinning
A common error in crystalisation in which two crystals grow
out of one another or next to one another, and their crystal lattice is
oriented differently from one another.
