Buffy Acacia
Diamonds have many wonderful propertiesMinerals have many unique properties, from their ability to make light shine like a rainbow to being harder than any other substance on Earth. These properties, along with centuries of marketing efforts by those who mine or cultivate them, give minerals a powerful influence on the human psyche. As fine jewelry trends slowly return to watchmaking trendsBeautiful colored gemstones are making a comeback. If you want to make an informed buying decision, here’s what you need to know about non-diamond gemstones.
About natural and synthetic gemstones
At first glance, The pros and cons of artificial stone The question is obvious. Of course, mined stones provoke a more romantic response to the natural wonder of the earth’s treasures, but lab-grown versions are chemically identical and much cheaper. Labor must also be considered, as the process of certifying ethical mining practices is not as strictly enforced as it was for diamonds in the past decade, so trust becomes a key factor to avoid worker exploitation. However, lab-grown gemstones produce almost five times the carbon emissions of mining, so nothing is perfect. Watch brands don’t usually disclose whether their gemstones are natural or lab-grown, so ask directly.
Sapphire and Ruby
Sapphire and ruby are both varieties of the mineral corundum, which is a crystalline form of aluminum oxide. The only measurable difference is that ruby is colored red by chromium impurities, while all other colored corundum is considered sapphire. Colorless sapphire crystal of the watch The red rubies used as bearings in the movement are both lab-grown corundum, a technology that has been around since the late 1800s.
In the field of jewelry and decorative watches, sapphires are best known for their deep blue color produced by titanium and iron. The most highly valued blue stones are Kashmir sapphires, which come from depleted mines in northern India, and Ceylon sapphires from Sri Lanka. Today, most natural sapphires are mined in Australia, but they can be found all over the world. Sapphire’s amazing color gradation is best known for the Rolex rainbow bezels, which use natural stones. Particularly popular today is the padparadscha sapphire, which is mined in Sri Lanka and Madagascar and is valued for its salmon pink and orange hues. With a Mohs hardness of 9, it is the third hardest mineral after moissanite and diamond.
Emerald
Throughout history, the word emerald has been applied to just about every green gemstone imaginable. It’s only in the last century or two that gemological research has clarified what emerald actually is and revealed that many famous “emeralds” throughout history are actually lookalikes. By modern standards, emerald is a green variety of beryl colored by chromium or vanadium. Without these two trace elements, any greenish beryl would be considered aquamarine.
What makes emeralds absolutely unique is that they are highly inclusive, meaning they have many internal fissures and impurities that reduce their transparency. While other crystals are generally considered to be of lower quality if they have inclusions, emeralds are praised for having beautiful “jardins” (gardens in French). That being said, truly natural emeralds that are clean to the naked eye still command very high prices due to their rarity, and nearly all emeralds on the market are treated with oil to fill in the fissures and increase clarity. Lab-grown emeralds can be difficult to distinguish, as they can be completely transparent or have their own jardins, depending on how they are made. Currently, the most valuable emeralds are mined in Colombia. Emeralds have a hardness of 7.5 to 8 on the Mohs scale, but are sometimes considered delicate due to their internal fissures.
Beryl
Emerald is a type of beryl, but there’s a lot more to know about beryl in general. Emerald is rare, but other types can be found under a wide variety of trademark names. The most common and popular is aquamarine, which has very few inclusions and is usually fairly inexpensive. Pink-orange beryl is called morganite, white beryl is called goshenite, and my favorite is the yellow/golden beryl known as heliodor. The rarest is the red beryl called bixbite, which is about 100 times rarer than emerald, but doesn’t seem to be as popular.
Tourmaline
Tourmaline is affectionately known as the trash can of minerals due to its tendency to absorb impurities during formation. As a result, tourmaline is actually a very complex mineral, but most of its pure form is jet black and opaque. However, when tourmaline crystals grow in the right conditions, they can exhibit a wide variety of beautiful colors. Like beryl, the most popular tourmaline colors have their own trademarks, such as rubellite for red tourmaline. Tourmaline is also a gemstone that often exhibits strong color zoning, and varieties ranging from green to white to pink are nicknamed watermelon tourmaline.
Paraiba tourmaline is an electric blue-green variety formed from manganese and copper impurities and has been found in small quantities in Brazil, Mozambique and Nigeria. Tourmaline can also be recognized by vertical striations in the stone, which indicate the pattern in which tourmaline grows into long hexagonal crystals. It is a relatively durable stone, with a Mohs hardness of 7 to 7.5.
Tanzanite
As the name suggests, tanzanite is only found in an area of about 14 km² in Tanzania. Tanzanite exhibits an effect called trichroism, which means that it can change color from blue to purple to wine red, depending on the orientation and angle of light passing through it. This effect is accentuated by geometric cuts such as cushion, pear and trillion. It was introduced to the market by Tiffany in 1968, but has rapidly grown in popularity in recent years. Tanzanite is a type of the mineral zoisite, but other varieties have never received as much attention as tanzanite. The mining process causes a lot of damage to these stones, so it is rare to find gemstones that are crack-free and clean to the naked eye, and the stone itself only has a Mohs hardness of 6 to 7.
garnet
Garnets are likely to be considered semi-precious due to their abundance, but there are many varieties that far surpass other gemstones in value and popularity. Almandine garnets are the most common and usually have the blood red color we strongly associate with them. Hessonite garnets have brown to orangey hues, while tsavorite garnets and demantoid garnets have bright green colors and are the most highly prized. Mint-colored garnets were originally discovered alongside tanzanite and were ignored for decades, but have recently entered the market in the form of beautiful cut gems and are revered. The various forms of garnet vary in hardness, but typically fall on the high end of the Mohs hardness scale, between 6 and 7.
quartz
Formed from silicon dioxide, the most common mineral on Earth, quartz is remarkable. In its applications in jewelry and watchmaking, it is often referred to as “rock crystal” to dispel the stigma of its abundance, as well as its association with quartz watch movements. Beautiful carvings are made from transparent quartz. Quartz on the watch faceit is a great natural alternative to glass. Citrine is a variety of pale yellow quartz that grows naturally into large crystals, but is very rare in the wild. Most of the yellow and orange quartz sold as citrine is actually amethyst that has been heat treated to change its original purple color.
Quartz’s microcrystalline structure affects its transparency; if it is slightly translucent it is called chalcedony, if it is opaque it is called jasper or chert. The most common chalcedony in watchmaking is undoubtedly onyx, which forms thick, distinct bands of black and white. The white is usually removed and black is used instead. The black usually has a beautiful inky polish. Red carnelian and green chrysoprase are other types of chalcedony used in watch decoration. All types of quartz tend to be around 7 on the Mohs hardness scale.
