"Opal is an amorphous silica gemstone containing water, mainly composed of silicon dioxide and water (SiO2-nH2O), and is also known as opal, opal, and shimmering cloud.
Opal, with its fascinating rainbow of colors, was once regarded as a top gemstone, and at that time it was believed to be a gemstone that brought good luck by bringing together small particles of various colors, such as rubies, sapphires, and green gemstones.
"Reasons for Opal's color change
"The internal structure of an opal consists of regular, nearly equal-sized spheres of silica arranged in a three-dimensional arrangement. These spheres and the gaps between them form a natural grating, a phenomenon called "diffraction" of light.
With the change of light source and people's observation angle, you can enjoy the flexible and changeable rainbow colors, which is the opal's "play of color"phenomenon. The final effect of play-of-color depends on the size and consistency of the arrangement of the silica spheres.
"Types of Opal
"Opal can be divided into two types: one has a play-of-color effect and is called "Precious Opal"; the other has no play-of-color effect and is called "Common Opal".
Depending on the color of the body of the opal, it can be divided into several categories: black opal, white opal, and fire opal. Descriptions such as "Black Opal" or "White Opal" refer to the color of the background of the body color that shows the variegated effect; Black Opal has a darker body color, so the variegated effect will have a more obvious contrast, and the color will be more vivid and eye-catching.
"Formation and origin of "Opal
Opals are formed when silica containing water is deposited in rock cavities and fissures at low temperatures (about 50 degrees Celsius). It is also possible for "Opal" to penetrate deep into plant and animal tissues or fossils within the strata to form fossilized "Opal".
Opal was mined near Czerwenitza in Slovakia from Roman times until the discovery of Australian mines at the end of the 19th century, and was first discovered in 1872 at Listowel Downs in central Queensland, Australia.
Currently, the most important sources of Opal are Australia, which produces White Opal and Black Opal, and Mexico, which produces clear Water Opal and Fire Opal, as well as Ethiopia, which is an important producer of Opal.
Factors affecting the value of Opal
"The quality of an Opal is determined by a number of factors, including the color of the background and the effect of variegation. Generally speaking, the darker the background, the brighter the variegation and the higher the value. Black opals are more expensive than white opals, and opals with vivid variegation are worth more, with red being the most popular color among variegation colors.
Australian Opals are much more expensive than Mexican Opals due to the fact that Australian Opals are more stable, while Mexican Opals can dehydrate when exposed to air for long periods of time.
Wearing and Preserving Opals
"Opal is a very fragile gemstone with a hardness of only 6 on the Mohs scale, softer than airborne dust. It should be kept away from wear and tear, heated, dry, and high-temperature storage environments, direct sunlight or other bright light, and contact with any chemicals and detergents, including perfumes and hairsprays, and should not be worn in the shower with Opal jewelry.
When storing, store with a wet cotton ball or a dish of distilled water to avoid cracking or splitting due to dehydration. Avoid ultrasonic cleaners and steam cleaners, and use only a damp or dry cloth for cleaning.
Famous Pieces
Chopard's Red Carpet High Jewelry collection includes a striking Flora Black Opal ring, inspired by mythology and nature. The 26.43ct curved, egg-shaped black opal has a distinctive blue-green hue, and the variegated colors are like a dreamy ocean, perfectly interpreting the theme of Paradise.
Tiffany Ribbon Brooch
Tiffany's 2019 Blue Book High Jewelry collection, "Jewel Box," features the striking Ribbon Brooch, inspired by the white ribbons that adorn Tiffany's gift boxes. The designer lays out a naturally stretching 'ribbon' of baguette-shaped stones, with a 37ct black opal wrapped around the center, evoking the surprise moment of opening a gift.
Boucheron White Opal Necklace Brooch
Boucheron launches a white opal necklace from its "Holographique" High Jewelry collection in 2021. The designer has created a dancing "fighting fish" in a dazzling array of colors, using custom-cut white opal to line the scales of the fish in relief; the tail fin is adorned with slices of curved white opal and framed by magnificent diamonds, giving it a streamlined shape that is reminiscent of a "fighting fish". The tail fin is adorned with curved white opal slices and set with gorgeous diamonds, giving the necklace a streamlined shape that is reminiscent of a "fighting fish" swimming freely in the ocean, full of natural vitality. The entire necklace consists of 14 strands of opal beads, using white opal flat beads with a total weight of over 1,500ct, echoing the color of the main stone.
The most eye-catching feature of the necklace is a 71.69ct curved white opal from Ethiopia, which can be seen as a variegated blue-green color on the surface, creating a dream-like oceanic light. In this piece, the designer has cleverly hidden a convertible structure that allows the "Fighting Fish" to be dismantled and worn independently as a brooch, offering a wealth of possibilities for accessorizing.
Van Cleef & Arpels White Opal Brooch
Van Cleef & Arpels Van Cleef & Arpels presents the Déesse Mercure White Opal Brooch in the 2021 Sous Les Etoiles High Jewelry collection, inspired by the vastness of the starry night sky, a fusion of poetic fantasy and mythological legend, whose name means "Goddess of Mercury" in French.
The goddess holds in her hand a curved 5.1ct white opal, a gemstone chosen to represent Mercury - the smallest planet in the solar system by mass and the closest to the sun, Mercury's thin surface atmosphere is often obscured by the sun's rays, making it difficult to observe, often at sunrise or sunset. White Opal is the most transparent and hazy gemstone in terms of color, and its color changes with the light, as romantic as Mercury.
Chopard Fire Opal Earrings
Chopard presents a pair of earrings in the Red Carpet collection featuring two Fire Opals totaling over 110 carats. These two stones have a curved teardrop cut with a clear texture and a curved cut shape that highlights the full orange color.
"Fire Opal is an orange-yellow to reddish-orange opal, colored by the element Fe, whose value is determined by the clarity and saturation of the stone, rather than by the variegated effects emphasized by white and black opals.
The designer has created a unique "claw-setting structure" for the two stones - the Fire Opal naturally climbs a gold vine on its side edges, connected by nearly 20 gemstone flowers, with curved pistils of manganese alumina garnet and yellow sapphire echoing the color of the Fire Opal, and petals of brilliant-cut diamonds. The floral element is also incorporated in the design of the earrings, which become an extension of the vine-shaped setting.