A moody and rather psychedelic mid-80s US rock band. Most of the band went on to become Mazzy Star, when original singer Kendra Smith was replaced by Hope Sandoval.

Opal are oft-associated with the paisley underground tag, among other bands seemingly influenced by both The Velvet Underground and The Doors. See also: Rain Parade, Dream Syndicate

Opal only have one proper album to their name, "Happy Nightmare Baby". They also have a far superior (but unfortunately nigh on impossible to track down) compilation titled "Early Recordings" which is one of this humble noder's favourite records of all time.

Opal is a silica mineral, like chalcedony, but it has a lot of water in its structure and is more like a hardened gel than a mineral with a crystal structure of molecules in rows. Though opals are found all over the world, Australia is the biggest source (including finds like Big Ben, a stone of over 4,000 carats).

Gemstone opal is the precious kind mentioned in Webster 1913's definition, and it is divided into "white opal," "black opal," "fire opal," and sometimes "water opal." What makes all of these "precious" opal" is the fire, a type of color play with flashes of color coming from little spheres of silica suspended in water inside the stone. The more red/orange the fire, the more expensive the stone will likely be. (Though blue/green fire has its own appeal.)

  • White opal is the most common -- a milky white background with flashes of other colors. This is what most people think of when they think of opal.
  • Black opal refers to opal with a black background (some dark-but-not-black stones are called "semiblack" opals). This is the rarest and most expensive type of opal.
  • Fire opal doesn't really look like other opals -- it is more transparent and has little to no fire (the name comes from the color of the whole stone, which is red-orange). Fire opals could usually pass for a reddish topaz, and they are usually cut faceted, unlike opals with fire which don't need anything to make them look showy.
  • Water opal is rare and little-known; it is a completely colorless opal with fire.
Opal is sometimes found in thin sheets attached to some other type of rock, narrow seams running through them, or just flecks of opal through ironstone. It can be sold this way, attached to or scattered through the "motherstone," and this is called "boulder opal." Often these are just meant as decorative mineral specimens, but boulder opal can also be made into jewelry.

Because of its softness and the thin layers available, opal is often made into doublets or triplets, where a layer of opal is either a) covered with some transparent material to protect its surface; b) layered on top of some other material to make it look darker and the fire show up more; or c) layered with several layers of opal to give the appearance of a thicker stone. The glue in these doublets and triplets has been known to sometimes change color over time. Another occasional problem is that the stone dries out, losing the water in its structure; some experts recommend soaking the stone in water briefly every so often to prevent this.

Thanks to Siobhan for additional info.

Minerology

Opal is primarily composed of non-crystalline silica (SiO2) with five to ten percent water. It is formed near the Earth's surface in volcanic rock, as water dissolves silica and percolates into cavities and cracks in the hot rock, then evaporates.

As a result of this non-rigid, non-crystalline structure, opal is brittle and breaks and scratches easily. It has a mineral hardness of only 5 1/2 to 6 1/2. However, its unusual beauty makes it extremely popular as a gemstone. Microscopic silicon and oxygen spheres in the stone, which are roughly equal in size and distribution in gem-quality opal, has the effect of diffracting light at various wavelengths and angles, creating a rainbow of colors as the stone is moved under light. Certain colors may also be produced by iron (yellow and red) or magnesium (green and blue) oxides within the stone. This phenomenon is called "play of color" or "opalescence" and varies greatly from stone to stone; larger splotches of color result in a more desirable and expensive gem.

Black opal is most popular and treasured, but opal comes in dozens of colors and varieties. White opal has a light background and pastel colors; crystal opal has a colorless background; fire opal has a translucent yellow, orange, or red background color. Jelly or water opal is colorless and transparent but has very little play of color. Solid opals (cabochons) are most valuable, but the desired color effects can also be produced by combining a thin strip of opal with a colored backing (doublet) to reduce its transparency or additionally with a clear quartz layer (triplet). The quartz layer protects the brittle opal and is ideal for rings and other "high contact" jewelry.

Certain opals may unpredictably develop internal cracks when exposed to a sudden change in light, heat, and/or humidity, or when it is subjected to vibration during cutting and polishing of the gem. This condition is called "crazing" and much care must be taken to keep stones stable while preparing a gem.

History

Opal's name originates in the Greek word opallios, meaning "to see a change of color" and a modification of the Sanskrit name for the gem, upula. The Roman historian Pliny described opal as "made up of the glories of the most precious stones. To describe it is a matter of inexpressive difficulty: There is in it the gentler fire of the ruby, the brilliant purple of the amethyst, the sea-green of the emerald, all shining together in an incredible union."

Opal was treasured in the England of Queen Elizabeth I and was described by Shakespeare in Twelfth Night as the "queen of gems." However, the 1831 novel Anne of Geierstein by Sir Walter Scott described it as a stone of evil, which shone red when Anne was angry, blue when sad, and green when happy, finally fading to ashen grey when she died. Opal had difficulty shaking this reputation until Queen Victoria made a present of opal jewelry to her children, making the stone popular again.

Mythology

The Romans considered opal a symbol of hope and purity, while the Greeks thought it bestowed the power of foresight and prophecy. The Arabs believed that opals made their wearer invisible and that they were fallen from heaven in flashes of lightning, making it sacred. The country of India had a not-dissimilar legend, that the gods Brahma, Vishnu, and Shiva once fell in jealous love for the same woman and bestowed upon her the colors blue, gold, and red to distinguish her as their own. She died nevertheless, and the Eternal took pity on her and transformed her into an opal stone with all three colors.

In medieval Europe, opal was believed to maintain a strong heart, prevent fainting and infection, and cleanse the air. However, after the Black Death began to sweep across the continent, the gem was sometimes believed to be the cause of death due to its change in appearance and luster. (In actuality, any color change was probably a symptom of death, due to the high heat sensitivity of the stone.) Even today it is sometimes considered bad luck to wear opals, at least if it isn't your birthstone.

The aborigines of Australia believe the opal is a half-serpent, half-human devil lurking in the ground and luring mean to their deaths with colorful flashes of magic. However, the miners in that country have a legend that a huge opal controls the stars and human love, as well as the gold in the ground.

Today

The principal source of black opals today is Australia, while fire opals are mined and sold primarily in Mexico. Opal is also mined in Nevada and the nearby United States, Brazil, Honduras, Guatemala, Nicaragua, Japan, and Ireland. Tanzania and Ethiopia recently discovered sources of opal as well.

Synthetic opal has been developed throughout the twentieth century and laboratory opals are now of very high-quality. These synthetic stones are made of exactly the same material as natural stones and under very similar conditions, first arriving on the open market in 1974. A skilled gemologist must inspect a stone under a microscope to distinguish a synthetic opal from a natural one.

Opal is the birthstone for the month of October (together with tourmaline) and is the symbolic gemstone for the 14th and 34th wedding anniversary.

Amy Lowell (1874-1925)

from Pictures of the Floating World (1919)

You are ice and fire,
The touch of you burns my hands like snow.
You are cold and flame.
You are the crimson of amaryllis,
The silver of moon-touched magnolias.
When I am with you,
My heart is a frozen pond
Gleaming with agitated torches.

O"pal (?), n. [L. opalus: cf. Gr. , Skr. upala a rock, stone, precious stone: cf. F. opale.] Min.

A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity.

⇒ 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. 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.

 

© Webster 1913.

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