I.D.
bracelet: I.D. is short for
"Identification", so an I.D.
bracelet is simply a curved plate
engraved with the name or initials
of the person wearing it.
IGI:
Stands for the "International
Gemological Institute". It is the
largest independent
gem
certification and appraisal
service in the United States.
Igneous:
A substance produced under
conditions involving intense heat,
such as that which is found in
volcanoes. Igneous rock is rock
formed by solidification from molten
magma.
Import:
The act of bringing or carrying in
goods from an outside source for
trade or sale, especially in regards
to goods from a foreign country.
Inclusion:
A naturally occurring flaw, (feather,
fracture,
fissure,
carbon spot, or
cloud), within a
diamond or other stone. The test
for
clarity looks for these flaws.
Indicolite: Blue
Tourmaline.
Ingot:
Metal cast into a bar or other
shape.
Inlaid:
Past tense of Inlay.
Inlay:
A decorative technique in which part
of the surface of a piece of
jewelry, furniture, or ceramic
is cut away and stone,
mother of pearl, or some other
substance is imbedded into the
hollowed-out area so that it is
level with the surface of the piece.
This is often seen in the decoration
and enhancement of acoustic guitars. See also
channel inlay.
Intaglio:
Italian for "carving", an Intaglio
is a carved
gem wherein the design is
engraved or carved into the object
so that it sits below the surface
plane of the material, as opposed to
a
cameo in which the design is
raised from it's background, in
relief. This technique was often
used for seals, which made a raised
impression in wax used to seal a
letter or authenticate a document.
It was commonly attached to watch
fobs, since the watch
fob is a good manner of carrying
a seal. Once seals fell out of
common use, the intaglio tended to
face out to the viewer rather than
down as on a seal. Some of the most
commonly found
Victorian intaglios were carved
in
carnelian, an orange-brown
variety of
chalcedony.
Invisible Set: A method of
setting square
gemstones side by side in two or
more rows within a
metal border or frame so that
they are flush against one another
with no
metal separating them.
Iolite:
(also called dichroite or water
sapphire). A
silicate of
alumina, iron,
and
magnesia which is usually
violet-blue, but can be deep blue,
light blue-gray, and yellow-white.
Makes a beautiful
transparent
gemstone which is remarkable for
its
dichroism.
Iridescent: A display of
lustrous rainbow-like colors. The
colors seen in an oil slick or
mother of pearl are good
examples of iridescence. The
spectrum of colors change as the
observers viewing position is
altered. Synonymous
with "Pearlescent".
Iridium:
A
metal of the
platinum family often
alloyed with
platinum to improve workability.
Pieces marked "80% Plat. 20% Irid"
would indicate that the
alloy is 80 %
platinum and 20% iridium.
Iron:
The most common
metallic
element which usually appears
dark brown, from
oxidation or impurity, but when
pure is silvery-white. Iron is found
abundantly in nature, usually in
combined forms such as
hematite, limonite, magnetite,
and taconite. It is frequently
alloyed in a wide range of
important structural materials like
cast iron, steel, and wrought iron.
It is easily oxidized (rusted) by
moisture, and is attacked by many
corrosive agents.
Iron
Pyrite: See
Pyrite.
Irradiation: The process of
bombarding a
gemstone with X-rays, gamma rays
or streams of subatomic particles in
order to change the stone's color.
Ivoride:
See
French Ivory.
Ivorine:
See
French Ivory.
Ivorite:
See
French Ivory.
Ivory:
A hard, smooth yellowish-white
substance usually referring to
elephant tusks, but also embraces
walrus tusks, narwhal (an
artic toothed whale having a
black-spotted whitish skin and in
the male, has a long spiral tusk)
and whales tooth. These ivory
sources would be protected in most
places.
Ivory,
French: See
French Ivory.
