13th April 2018 Guides
This is the final part of our series of guides to birthstones which gives an overview on October, November, and December. To read part one click here, part two here and part three here. Birthstones are a fantastic way to add a special meaning to jewellery and make great gifts to mark a birthday, anniversary, graduation or other memorable occasions. They can be incorporated into rings, necklaces, pendants, bracelets and more. Paired with diamonds, they can add a splash of colour and variety to your jewellery piece. So read up on all the birthstones with our handy guide:
The name “tourmaline” comes from the Sinhalese words tura mali, which mean “stone of mixed colours.” As its name implies, tourmaline stands apart from other gems with its broad spectrum of colours in every shade of the rainbow. Egyptian legend tells that tourmaline found its famed array of colours when, on its journey up from the earth’s centre, it passed through a rainbow. Because of its colourful occurrences, tourmaline has been confused with other gems throughout history. No two tourmaline gems are exactly alike, which makes this a one-of-a-kind gift for any individual—especially someone celebrating an October birthday or an eighth wedding anniversary. With a wide variety of colours, qualities and sources available, there’s tourmaline to suit a range of styles and budgets. Like diamonds, tourmaline is evaluated by the criteria of colour, clarity, cut and carat weight.
The name “opal” originates from the Greek word opallios, which meant “to see a change in colour.” The Roman scholar Pliny used the word opalus when he wrote about this gem’s kaleidoscopic “play” of colours that could simulate shades of any stone. Opal has been a good luck charm for centuries—though recent superstitions consider it lucky only for people born in October, and unlucky to anyone else. However, opal’s kaleidoscopic play-of-colour can suit many changing moods and tastes to make this gem appropriate for anyone. It is also the traditional gift to celebrate 14th wedding anniversaries. Like diamonds, opals can be evaluated by colour, clarity, cut and carat weight, but these unique gems also have several additional conditions to consider. Colour is the key factor of opal quality: both the background “body colour” and the flashing “play-of-colour.” Dark backgrounds provide more contrast against vivid play-of-colour, making black opal more highly valued than milky white varieties. Play-of-color is measured on a brightness scale of 1 to 5, from faint to brilliant. Warm colours like red and orange are generally rarer and more valuable than common blues and greens, although colour range and coverage also play a role. Pattern is another factor unique to opal. Descriptive names like stained glass, peacock, rolling fire and Chinese writing distinguish opal patterns. Gemologists typically prefer large, concentrated patches over small specks.
Through much of history, all yellow gems were considered topaz and all topaz was thought to be yellow. Topaz is actually available in many colours, and it’s likely not even related to the stones that first donned its name. Since topaz was recognized as more than just a yellow gem, it has become fairly common and therefore rather inexpensive. It can be judged along the same parameters as diamonds. In fact, colourless topaz is increasingly popular as an inexpensive diamond alternative. When buying topaz, realize that this gem is most often treated with irradiation to produce desirable colors—particularly blue. Because these processes so closely resemble how topaz forms in nature, there is practically no way to determine whether a stone has been treated. Visit a credited jeweller who can help you select a quality gem.
November’s second birthstone, citrine, is the variety of quartz that ranges from pale yellow to brownish orange in colour. It takes its name from the citron fruit because of these lemon-inspired shades. Citrine is one of the most affordable and abundant gemstones on the market. Even fine, large gems are modestly priced, which means everyone can find citrine to fit their budget. These gems can be evaluated by the same factors as diamonds. Because the majority of citrine gems on the market have been heat treated—and because it takes an expert to detect these enhancements—it’s wise to shop with a credited jeweller who can help you choose the best gem. The finest citrine gems are saturated with yellow, orange and reddish hues, while stones of lower value appear pale or smoky. Earth-tones of amber brown are also increasingly popular.
December has three birthstones to choose from, each known for its distinctive blue shades. Turquoise but the most associated, then Zircon and Tanzanite recently added to the lineup.
Admired since ancient times, turquoise is known for its distinct colour, which ranges from powdery blue to greenish robin’s egg blue. It’s one of few minerals to lend its name to anything that resembles its striking colour. Turquoise is one of few gems not judged by the 4Cs of diamond quality. Instead, the main factors that determine its value are colour, matrix, hardness, and size. The most prized turquoise colour is a bright, even sky blue. Greenish tones can lower the value of a stone, although some designers prefer it. Some turquoise – particularly the material mined in the American Southwest – contains remnants of its host rock, known as matrix. These splotches decrease a gem’s value. Although it can create an attractive “spider web” pattern, unblemished varieties command higher prices. The porosity, texture, and hardness of turquoise vary greatly. Fine-coloured turquoise that’s too soft or chalky will lose colour – and value. Course, the porous material is usually treated to make it stronger, smoother and shinier.
Zircon is an underrated gem that’s often confused with synthetic cubic zirconia due to similar names and shared use as diamond simulants. Few people realize that zircon is a spectacular natural gem available in a variety of colours. Whether you’re buying blue zircon to celebrate a December birthday, or selecting another shade just to own a gorgeous piece of earth’s oldest history, zircon offers many options. A wide range of colours at relatively low cost makes zircon a popular gem with collectors. Zircon is often cut in the brilliant style to showcase its diamond-like lustre and fire. Facets must be cut carefully (to avoid chipping this brittle stone) and properly (to avoid the blur caused by zircon’s strong double refraction).
They are the last gemstones to be discussed, if you’re interested in incorporating them into your jewellery piece, or just want to find out more, don’t hesitate to get in touch through the contact form or by phone.
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