October Birthstone - the Color of the Opal
The name opal actually means "to see a change in color." The opal occurs
in several types of color. The White opal has a white body color with
pastel glints of rainbow color. Black opal has a blue, gray or black
body color. The black Boulder opal contains ironstone. Crystal or water
opal is The transparent or colorless opal contains brilliant flashes of
color within it. Fire opal is a transparent or a translucent opal with a
yellow, orange or red body color that may also have a flash of color.
Definition of the
Opal, the October Birthstone
Definition of Opal, the October birth stone: The word Opal is derived
from the Latin word "opalus" which means "a stone".
The precious opal presents a peculiar play of colors of delicate tints,
and is highly esteemed as a gem. One kind, with a varied play of color
in a reddish ground, is called the harlequin opal. The fire opal has
colors like the red and yellow of flame. The Common opal has a milky
appearance. Menilite is a brown impure variety, occurring in concretions
at Menilmontant, near Paris. Other varieties are cacholong, girasol,
hyalite, and geyserite. The crystal structure
of the Opal (hydrous silicon dioxide), the October birthstone, is
Amorphous. Opal miners restrict use of the term opal to precious opal,
calling material that does not show a good play of colors, 'potch'.
October Birth stone - the History of the Opal
For those who were born in the month of October the Opal is the
traditional birthstone. The history, myths, legends and folklore
surrounding the magical properties of different birthstones have been
handed down through the ages and from different civilisations. This
subject has been documented separately in the History of Birthstones section
which can be accessed by the link at the top of the page.