_ The opal has suffered from an unfortunate reputation as being an evil stone and bearing ill omen. There are several explanations for the ominous superstitions surrounding this wonderful gem, but the evil associations have never been merited and probably resulted from a careless reading of Sir Walter Scott's Anne of Geierstein.
Among the ancients, opal was a symbol of fidelity and assurance, and in later history, it became strongly associated with religious emotion and prayer. It was believed to have strong therapeutic value for diseases of the eye, and when worn as an amulet, it would make the wearer immune from all such diseases as well as increase the powers of the eyes and the mind. Many believed that to the extent the colors of red and green were seen, the therapeutic powers of the stones with those colors-red and green-the powers were also to be enjoyed by the wearer, the power to stop bleeding (ruby) and the power to cure kidney disease (emerald). The black opal was particularly highly prized as the luck stone of anyone lucky enough to own one.
This stone, whose brilliant colors resemble the colors of the fall, is unique among the gems, displaying an array of very brilliant miniature rainbow effects, all mixed up together. This is opal's most distinctive characteristic. This effect is created by opal's formation process, which is very different from that of other gems. Opal is composed of hydrated silica spheres. The mini rainbows seen in most opals result from light interference created by these spheres. The arrangement of the spheres, which vary in size and pattern, is responsible for the different colors seen.
Opal is usually cut flat or in cabochon since there is no additional brilliance to be captured by a good faceting job. Color is everything. The more brilliant the color, the more valuable the gem. This is probably truer of opal than any other stone. The more beautiful the stone and its color, the more it will cost.
The finest of all opals is the black opal. Black opals are usually a deep gray or grayish black with flashes of incredibly brilliant color dancing around within and about the stone as it is turned. One must be careful when purchasing a black opal; to ensure it is not a doublet or triplet, a stone composed of two or three pieces of stone glued together. There are many such doublet and triplets in the market because of the black opal's rarity, beauty, and extremely high cost. A natural black opal the size of a lima bean could cost as much as $50,000 in today's market. The black opal doublet and triplet provides an affordable alternative to the one who loves them but can not afford them. Beware, this also presents an opportunity for misrepresentation that can be very costly to the consumer.
Generally speaking, the purity of color, absence of dead spots, called trueness, flawlessness, and intensity or brilliance of color are the primary variables affecting value. Those opals with an abundance of red are usually the most expensive, and those strong in blue and green are equally beautiful but not as rare, so their prices are somewhat less. Some opals are very transparent and are classified as "jelly", "semi-jelly", or "water" opals.
One word of caution must be offered. Opals require special care because some tend to dry out and crack. Avoid exposure to anything that is potentially drying. Bathing an opal occasionally in olive oil or coating it with olive oil when not in use will help preserve it. But do not soak any opal in oil because soaking some opals for only a few hours can cause them to lose some or nearly all of their fire.
Tourmalines are gems with an incomparable variety of colors. The reason, according to an old Egyptian legend, is that the tourmaline, on its long journey up from the center of the Earth, passed over a rainbow. In doing so, it assumed all the colors of the rainbow. And that is why it is still referred to as the 'gemstone of the rainbow' today.
The name tourmaline comes from the Singhalese words 'tura mali'. In translation, this means something like 'stone with mixed colors', referring to the color spectrum of this gemstone, which outdoes that of all other precious stones. There are tourmalines from red to green and from blue to yellow. They often have two or more colors. There are tourmalines which change their color when the light changes from daylight to artificial light, and some show the light effect of a cat's eye. No two tourmalines are exactly alike.
This gemstone has an endless number of faces, and for that reason it suits all moods. No wonder that magical powers have been attributed to it since ancient times. In particular, it is the gemstone of love and of friendship, and is said to render them firm and long-lasting._
Iindividual color variants have their own names. A tourmaline of an intense red is known as a 'rubellite', but only if it continues to display the same fine ruby red in artificial light as it did in daylight. If the color changes when the light source does, the stone is called a pink or shocking pink tourmaline. Blue tourmalines are known as 'indigolites', yellowish-brown to dark brown ones as 'dravites' and black ones as 'schorl'. One particularly popular variety is the green Tourmaline, known as a 'verdelite'. However, if its fine emerald-like green is caused by tiny traces of chrome, it is referred to as a 'chrome tourmaline'. The absolute highlight among the tourmalines is the 'Paraiba tourmaline', a gemstone of an intense blue to blue-green which was not discovered until 1987 in a mine in the Brazilian state of Paraiba. In good qualities, these gemstones are much sought-after treasures today. Tourmalines from Malawi with a vivid yellow color, known as 'canary tourmalines', was previously very scarce, but now is beening very well represented in the endless spectrum of colors boasted by the 'gemstone of the rainbow'.
Yet the tourmaline has even more names: stones with two colors are known as bicolored tourmalines, and those with more than two as multicolored tourmalines. Slices showing a cross-section of the tourmaline crystal are also very popular because they display, in a very small area, the whole of the incomparable color variety of this gemstone. If the center of the slice is red and the area around it green, the stone is given the nickname 'water melon'. On the other hand, if the crystal is almost colorless and black at the ends only, it is called a 'Mohrenkopf', (resembling a certain kind of cake popular in Germany).
Tourmalines are found almost all over the world. There are major deposits in Brazil, Sri Lanka and South and south-west Africa. Other finds have been made in Nigeria, Zimbabwe, Kenya, Tanzania, Mozambique, Madagascar, Pakistan and Afghanistan. Tourmalines are also found in the USA, mainly in California and Maine. Although there are plenty of gemstone deposits which contain tourmalines, good qualities and fine colors are not often discovered among them. For this reason, the price spectrum of the tourmaline is almost as broad as that of its colour.