There is the bright gemstone, which exhibits fire and brilliance like no other, and then there is also the white gemstone that also happens to be opaque, which holds its kind of beauty. If you are a fan of colored and colorless gemstones, you will love the top four opaque white gemstones for jewelry and other applications.
4 Colorless Gemstones for Jewelry
Pearl is considered an organic gemstone that has as much beauty and luster as mineralized gemstones. Pearls are hard objects found in oysters and freshwater mussels. They are eventually formed inside the bodies of oysters and mussels as a response to an irritant inside the body of the clam.
Chemically, pearls are made mostly of calcium carbonate. Over months or years, oysters and mussels release quantities of a mother of pearl over the said irritants, and the irritants are coated, creating the beautiful pearls that we know and love.
What does an ideal pearl look like?
An ideal set of pearls, for one, won’t look identical to each other. Be wary when someone offers you pearls that are all smooth and round like a machine polished them. If it’s too perfect and too consistent, you may be looking at a bunch of fake pearls instead of the real thing. Remember, too, that not all pearls are round.
Some of them may be more oval or tear-shaped. Some look so irregular that you may wonder if they are pearls at all. Remember, pearls are formed by oysters and are poured in molds in factories.
People are always on the lookout for large spontaneous pearls that are harvested from the wild.
Natural pearls are sought after because they are usually formed after many years, far longer than what pearl farms are willing to invest while waiting for their oysters and mussels to form pearls. Pearl farms are patient, but not that patient. Eventually, the oysters and mussels have to be harvested.
Moonstones are a class of feldspar that is gem-quality or high quality. Moonstones are related to jaspers (all colors). The superior quality of moonstone that makes it stand out in our list of opaque white gems is adularescence, or the otherworldly white glow observed at the center of a properly cut moonstone. The glow is due to the diffraction or bending of light when light strikes the moonstone’s surface. This schiller effect is observable just beneath the surface of moonstone.
Some moonstones also exhibit a second schiller effect called chatoyancy or cat’s eye. In rare instances, parallel tubular structures inside the gemstone also bend light so that a sharp contrast is made, dividing the hemispheres of the gemstone.
Because the main selling point of moonstones is adularescence, it has to be handled only by the most skilled cutters. The cutter has to first orient the moonstone across the plane where the adularescence is observed.
From that plane, the cabochon will be cut to maximize the schiller effect. The most significant source of moonstones today is Sri Lanka, followed by other countries that also produce many other precious stones like India, Burma, and Brazil.
White opal, also known as light opal, is the name used to describe a subtype of opal with a creamy white body.
Opal is a hydrated form of silica mineral and is most notable for its constant play of color. The play of color is the result of the interaction of the opal’s water content and the uniform silica structures inside.
Opals are harvested primarily in Australia, and the subcontinent provides over eighty percent of the world’s total opal supply. Opals are commonly cut into cabochons like other opaque gems to highlight the play of color and other positive attributes of the gemstone.
The water content of opal specimens can range from three percent to over twenty-one percent, depending on the specimen.
The exciting thing about opals is that they can occur almost anywhere and are not demanding gemstones at all. Large specimens of opal have been recovered in fissures of rocks, and it is one of the most affordable gemstones around.
There are two kinds of opal: common opal and precious opal. Precious opal is more expensive and is more sought after than common opal, which is usually combined with other minerals to increase its durability as an ornamental piece.
Mother of Pearl
Mother of pearl, or nacre, is the substance responsible for the formation of pearls in mussels and oysters. What makes this material impressive is that it has a schiller effect of its own (rainbow visual effect). Some oyster species are known to produce the hardest version of the nacre that beat the hardness of the nacre of freshwater mussels.
There should be no confusion – when the manufacturers of jewelry say that something was made with “mother of pearl” the manufacturer is probably referring to the shiny nacre lining of the oyster shell and not the pearls.
The mother of pearl is technically a biomineral, and this fact has intrigued scientists for so long. The deposition of nacre is necessary for the formation of pearls, and bivalves will only produce high-quality nacre if their environment is clear of toxins. The chemistry of the water is ideal.
This is why in Japan, freshwater pearl farmers following the more traditional methods of culturing pearls have to move their operations to remote rivers where the water quality is purer and better. It is said that pollution affects pearl farming, and with the state of our oceans and hydrologic systems in peril, it’s not surprising that pearl farms are having a tough time of it.
Before, the pearl mother was not in high demand until manufacturers started devising ways to take advantage of the nacre-filled layer of bivalves. What was previously considered a byproduct of pearl culture is now a year-round requirement of many industries, especially the industries that produce watches and other ornamental pieces.