A Comprehensive Guide to Gemstones
Once you’ve bought one piece of gemstone jewellery, it’s inevitable you’ll end up purchasing more. That’s largely because there’s a huge range of gems available, and each precious and semi-precious stone has its own unique appeal.
In this guide, we’ll be exploring:
- What gemstones are
- The history of gemstones
- How they’re formed, discovered, mined and cut
- How they’re used in jewellery
We’ll also examine some of the most popular gems; identifying what makes them so sought-after, and the history and symbolism behind each one.
What is a gemstone, exactly?
For a stone to be classified as a gemstone, it needs to be three things:
- Beautiful
- Rare
- Durable
Beautiful
Beauty is subjective, which makes it hard to measure accurately. However, most experts agree that, in order to be regarded as beautiful, a stone must have at least one of the following:
- Remarkable clarity or transparency
- A bright, strong colour
Flawlessness is another sought-after feature of a gemstone, but rather confusingly, a stone doesn’t have to be flawless to be regarded as a gem. For example, the surface of a turquoise gemstone is often marked with lines, but this is still regarded as beautiful, as it makes each piece unique.
Rare
All gemstones are rare, which means they can’t be easily found, unless you know where to look. Some stones are far rarer than others. For example, tanzanite is believed to be 1,000 times rarer than diamond. This affects the value – the rarer the stone, the more it’s likely to cost.
Durable
For a stone to be classified as a gem, it needs to be strong and hard. The hardness of a gemstone is measured using the Mohs scale; with 10 being the hardest and one being the softest. The Mohs scale is useful for jewellery collectors; for example, if you’re planning on wearing a bracelet every day, you might want to select a gemstone that’s high on the scale, as it’ll be more resistant to daily wear-and-tear.
A brief history of gemstones
Mankind’s love affair with gems has been going on for centuries. The earliest examples of gemstone jewellery were crafted around 25,000 years ago, but the stones weren’t just used for decorative purposes. Gems were also used to make weapons, and some people believed they had healing powers too.
The Ancient Egyptians frequently used gemstones in their jewellery; particularly lapis lazuli, carnelian and amethyst. There are plenty of examples of gemstone jewellery from ancient China too; though here, the favoured semi-precious stone was jade. In fact, gems were widely used all around the world, in locations such as Europe (particularly ancient Rome and Greece), and in India, to name just a few.
The popularity of these precious stones has never really diminished. Throughout history, gems have been worn by monarchs and wealthy merchants alike. They’ve functioned as valuable trade items to build relationships with other cultures, and have been used to decorate the home.
Gemstones have also become symbolic over time, and formed an important part of many different rituals. They were sometimes used to appease the gods, to accompany ceremonies regarding birth, marriage and death, or to act as talismans, offering protection to the wearer.
How are gemstones formed, discovered, mined and cut?
The formation of gemstones
Every gemstone is formed differently, and comprises a diverse range of elements. For example, amethyst is made up of silica, oxygen and iron – and without the right quantities of these three things (plus exactly the right level of heat and time), it simply wouldn’t be created. Interestingly, if you increase the heat, you’ll actually end up with citrine, not amethyst – as they’re both members of the quartz ‘family’.
Essentially, all gemstones require the following to form:
- Extreme heat
- Intense pressure
- A lot of time (millions of years)
In some instances, gemstones are formed many miles underground, where the pressure is a lot higher. The collision of tectonic plates can produce the required amount of pressure too.
Discovering gems
Most gemstones are hidden beneath the ground, so their discovery often relies on chance. Sometimes, they can be found in riverbeds. This gives gemstone-hunters a clue that there’s a deposit located somewhere upstream. On other occasions, miners locate gemstones accidentally, when they’re digging for other minerals.
Volcanic activity can sometimes push gems closer to the surface, so miners occasionally try searching in areas with volcanos. Ultimately, there’s always a bit of luck involved with finding a rich seam of gemstones in the ground.
Mining gemstones
The exact mining methods used to extract gemstones depends on the size of the company doing the mining. Large commercial mines will use industrial machinery to remove substantial quantities from the ground, whereas small-scale enterprises may use more modest, traditional methods.
Tunnel mining is the most common way to access gemstones. A vertical tunnel is dug downwards, then horizontal tunnels are created, which run off this central ‘spoke’ tunnel. The miners have to adjust their route to follow the gemstone seams, which means the tunnels seldom run in straight lines.
By contrast, open pit mining creates an enormous exposed hole in the ground, which enables miners to extract every gemstone in that area. After removing all the gems, the hole is refilled. This is an expensive, time-consuming way to mine, and isn’t as popular as tunnel mining.
Gemstones can also be found in riverbeds, so some miners stick to digging in these locations instead. It’s a cheaper way to search, but the quantity of gemstones found may be limited.
Cutting gemstones
When gemstones are removed from the ground, they look very different to the gems you’ll see in jewellery. They need to be cleaned, polished and cut before they’re suitable for use.
Some gemstones are cut into a dome shape (called a cabochon), while others are faceted – which means they have a number of precisely cut flat surfaces. The faceted cut enhances the sparkle by maximising the amount of light that can enter the gemstone, then reflect outwards.
How gemstones are used in jewellery
Gemstones are used in all kinds of jewellery. Here are just a few examples:
Rings
Some rings are solitaire, which means they only have one gemstone as a dramatic centre-piece. These gems are usually faceted, and cut in a range of different styles, such as the round brilliant cut, oval cut, or baguette cut. Other rings may feature a cluster of gems; either all the same type, or a mixture of different coloured gemstones, designed to complement one another.
Bracelets
It’s common for narrow bracelets to feature just the one sparkling gemstone, or to be inlaid with several gems, which cover its entire surface. Gems such as turquoise, jet and lapis lazuli offer a bright, bohemian look, while gleaming gemstones like amethyst, ruby and emerald are more commonly used for evening-wear.
Earrings
Earrings allow jewellery-designers to get really creative with gemstones. For example, drop earrings may feature just the one gemstone at the bottom, to create weight and a dramatic focal point. Sometimes, they’ll feature clusters of gems running along the entire length of the piece.
Necklaces
Necklaces, especially pendant necklaces, are statement items which frequently include bold, bright gemstones for maximum impact. For an expensive look, stones like sapphire and crystal are popular choices. They catch the light well, and highlight the natural movement of the necklace against the body.
The different types of gemstone – their history, meaning and uses
Nobody knows for sure how many different sorts of gemstones there are in the world. Walter Schumann’s Gemstones of the World lists approximately 200, but there could well be more. Some types are more desirable than others, and this is usually due to their colour, size and rarity.
Here’s a guide to 10 of the most commonly used gemstones in jewellery-making.
Crystal
Crystals have long been associated with healing. There’s evidence that the ancient Sumerians used them to make elixirs, and other cultures believed they had a variety of magical powers too. In 1609, Anselmus de Boodt (Rudolf II’s physician), a leading mineralogist of the time, suggested that crystals were linked to good or bad angels, and these theories prevailed until the Age of Enlightenment.
In the 19th century, psychics started to use crystals to manipulate emotions and responses, by pressing them against their subjects’ bodies. This led to modern-day crystal healing, and to this day, crystals are still purchased for this purpose.
The most prized crystals are those that are perfectly clear, and which sparkle in the light. Some people compare this gemstone to ice, which is unsurprising given the origin of the name. It comes from the Greek word krystallos, which means ‘coldness drawn together’.
You’ll often see crystal in fashion jewellery, as it complements a range of other gemstones, and is a more affordable alternative to diamond. It’s a popular choice of gemstone for fine jewellery too, and is used to enhance the beauty of other more expensive stones.
Topaz
Topaz is prized for its diverse colouring; with some stones being orange or yellow, and others being pink or even blue. The most sought-after type is called imperial topaz, which is orange with a pinkish hue. Blue used to be the rarest shade, but these days, jewellery-makers are able to enhance topaz’s colour artificially.
It’s thought that the word topaz originated in Topazios, which is a tiny island in the Red Sea (now named Zabargad). Rather confusingly, no topaz was ever mined there, but peridot was – and the two gemstones are often confused with one another. Other experts believe that the word comes from the ancient Sanskrit word ‘tapaz’, which means ‘fire’.
The ancient Greeks were fond of topaz, as they believed it gave them strength and resilience. During the Renaissance, Europeans thought that the gemstone provided protection against dark magic, while in India, it was believed that topaz promoted beauty, longevity and intelligence. In more recent years, imperial topaz was mined extensively in Russia, but only the tsars were permitted to own it.
Topaz is the birthstone for November, and is used in both fashion and fine jewellery. It’s the perfect gem for adding vibrant colour to a pair of earrings, brooch or necklace.
Sapphire
Sapphire has been associated with royalty for centuries. In ancient Greece, kings believed that wearing sapphires would protect them from harm. Clergymen from the Middle Ages wore sapphires as a symbol of heaven, thanks to their striking blue colour.
Their popularity and prestige haven’t diminished since then. When Prince Charles proposed to Lady Diana in 1981, he gave her a sapphire engagement ring – a piece of jewellery that was much admired at the time.
The word originates from the Greek sappheiros, which experts think actually refers to lapis lazuli. It’s a common mistake to believe that all sapphires are blue. While this is the most common colour, sapphires do come in other shades too. For example, orange-pink sapphires are called padparadscha, which is the Sinhalese (Sri Lankan) word for a lotus flower.
Sapphires can command a high price, especially if they’re a vibrant violet-blue. The most valuable sapphires tend to come from Myanmar, Sri Lanka and Kashmir. This is why this gemstone is often reserved for fine jewellery; as it adds an expensive note of allure to drop-earrings, pendants and bracelets.
If you’re born in September, then this is the stone for you, as it’s this month’s birthstone.
Ruby
Rubies often appear in popular culture; featuring in everything from Pretty Woman, to the colour of Dorothy’s slippers in The Wizard of Oz. They’re also a symbol of love and passion, which is why they’re a popular gemstone for Valentine’s Day gifts.
Its name derives from ruber, the Latin word for ‘red’. Ancient cultures prized it as much as their modern counterparts. For example, the gem is mentioned several times in the Bible, and in Sanskrit, it’s referred to as the ‘king of precious stones’. Thousands of years ago, Hindus believed that those who offered rubies to Krishna would be reborn as emperors.
People believed that rubies had other powers too. In India, it was thought that this gem promoted peace with enemies, and in Burma, warriors pushed rubies into their flesh to make them more powerful in battle.
The colour of the ruby plays a big part in determining its value. The most valuable are ‘Burmese rubies’, which are a bright shade of red. Some are almost orange in hue, while others are a dark purple-blue. Rubies are the birthstone for July.
Quartz
Technically, quartz isn’t a gemstone in itself. However, many popular gems, such as amethyst and citrine, are types of quartz, so it’s worthy of mention. Rose quartz is also classified as a gemstone, thanks to its attractive pink hue.
It’s the second most abundant mineral to be found in the Earth’s crust; beaten only by feldspar. Although it’s not rare or valuable, quartz is used in jewellery to complement other, more colourful gems.
In ancient times, it was used as a talisman against evil, and rose quartz was used in Roman seals to signify ownership. Quartz was also prized by physicians in the Middle Ages, and used in healing tinctures and potions. In the Americas, it was commonly used in jewellery-making, and was believed to balance the emotions.
As it’s not such a valuable gemstone, quartz tends to be used mainly in costume jewellery. Sometimes, it’s also placed alongside more expensive stones, such as sapphire.
Peridot
Peridot’s eye-catching colour makes it a desirable gemstone. In the past, it’s been confused with other gems, such as emerald and topaz. Nowadays, experts know the key differences that separate this stone from its other green-hued counterparts.
The ancient Egyptians valued peridot highly, and called it the ‘gem of the sun’. It’s also believed that Cleopatra’s renowned collection of emeralds was actually a selection of peridots instead. Various other cultures prized this gem too, with some believing that it had the power to ward off nightmares, particularly when set in gold.
Its name originates from the Arabic word faridat, which quite simply, means ‘gem’. Most of the peridot used in jewellery today comes from Arizona, though it’s also sometimes mined in China, Pakistan and Myanmar. The bright green stones are the most desirable, though they also come in yellow and brown shades too. It’s the birthstone for August.
Amethyst
This gemstone takes its name from a Greek myth. According to legend, Amethyst angered the god Dionysus after she drank too much red wine. She begged Diana to save her, so the goddess transformed her into a piece of quartz. Dionysus wept with guilt at the sight of her, and his tears fell into his glass of red wine. The wine spilled on the quartz, and turned the surface a light purple colour.
In addition to having its own myth, it’s been a firm favourite of royals throughout the ages. It was also popular with the clergy; in the past, bishops used to wear amethyst jewellery to symbolise Christ. Until recently, it was hard to find, and its rarity made it as valuable as diamond. However, plentiful supplies from South America made it more accessible to jewellery makers, and its value subsequently fell. In spite of this, it remains a sought-after gemstone, thanks to its beautiful purple-pink colour.
Amethyst is the birthstone for February.
Chalcedony
Chalcedony is a name that encompasses a variety of semi-precious stones, and it’s been used by humans for centuries. The earliest example was in some ancient tools discovered in Australia, which date back to 35,000 BC. It’s also been used to decorate palaces, and to make jewellery.
Nowadays, the most commonly used types of chalcedony are onyx, carnelian, agate and jasper. These attractive semi-precious stones are appreciated for their unusual striations, intense colours, and smooth surfaces when polished. They’re often used to complement other gemstones in necklaces, bracelets and earrings.
There is one type of stone that’s called true chalcedony, which is a milky grey-blue colour. It’s believed that the name comes from the Greek town Chalcedon.
Citrine
Citrine is actually a type of amethyst, which forms at a higher heat. Unlike amethyst, which is known for its pink colour, this gemstone usually has a yellow-gold hue, which is why its name translates as ‘lemon’ in French.
It wasn’t always called citrine, though. Prior to the 1500s, it went by the name yellow quartz, and was a popular choice of gem for jewellery. However, its uses extended beyond jewellery; in the 17th century, the Scottish people used it to decorate the handles of their daggers and swords.
Citrine experienced a surge in popularity in the 1920s, and features in many Art Deco pieces dating from this period. The finest examples tend to feature oversized citrine stones, which were designed to grab attention.
These days, citrine is regarded as a desirable, affordable gemstone. The most desirable gems are clear and lustrous, with a bright yellow to brown-red colour.
Spinel
Spinel is often red, which is why it’s so commonly mistaken for ruby. In fact, Sanskrit writings explicitly refer to this gemstone as the ‘daughter of ruby’ and praise its striking colour. Although rubies are often the more expensive stone, spinel is actually rarer. However, it’s usually found in larger sizes underground, which makes it more affordable.
Many of the finest spinel crystals originally came from central and southeast Asia, and were called Balas rubies. They were incorporated into royal jewellery and crowns, and often classified as rubies, when in fact they were an entirely different gemstone. The Black Prince’s ruby in England’s Imperial State Crown is actually a spinel, which is believed to originate from Afghanistan.
Like rubies, spinel comes in a variety of different colours; including bright orange, pink and deep purple. Hot-pink hued spinel is particularly valued, and this type usually comes from Myanmar. Very occasionally, the gemstone is also blue, but this colour is far rarer. It’s another August birthstone, which seems fitting, given its fiery, warm shade.
Finding the right gemstone jewellery
Some people invest in gemstone jewellery for aesthetic reasons. For example, a pair of vivid purple amethyst earrings might set off a particular dress for a special occasion, or you might be looking for a blend of pastel shades in a bracelet, which can be worn during the summer months.
Alternatively, you might like the symbolism behind the gems, or seek out a piece of jewellery that features your birthstone. It’s great to get a balance between all these things, and invest in jewellery that’s both attractive and meaningful. This makes it not only the perfect piece to wear, but also gives it sentimental value, making it an heirloom for the future.
Looking for gemstone jewellery? Shop our range of fashion jewellery and fine jewellery featuring a range of semi-precious and precious stones.