At Precious Earth, we are committed to sourcing only the highest-quality gemstones from trusted suppliers. Our mine-to-market approach ensures that our gemstones are made available to you at the best possible value. However, when looking for a gem to purchase, it is essential to understand which sources produce superior gemstones and which ones to prefer for a particular stone. It's also important to note that some gemstones hold a higher value than others depending on their origin, even if they may appear identical at first glance. In this guide, we take a deep dive into understanding the different sources of origin for precious stones, and how these origins play a key role in determining a gemstone’s value.
How Does a Gemstone’s Origin Affect its Value?
A gemstone’s origin is the geographical region or mine that it is extracted from. Some mines are known for high-quality specimens as the conditions there are favourable to produce gemstones with good grading. The presence of certain trace elements can lead to gemstones with deep colours, while certain conditions during their formation can produce exceptionally clear specimens. Some regions may even be rich in minerals like rutile or boehmite, which can lead to gemstones with asterism (star rubies and cat’s eyes) or high levels of silk. Further, some regions are even known for their inferior-quality gemstones and should be steered clear of, especially if you are a first-time buyer.
When a mine starts to run ‘dry’, and starts producing fewer high-quality specimens, the rarity can cause the value of individual gemstones to increase. If the mine entirely stops producing gemstones, the specimens already in the market find their value enhanced as well, as is the case with Kashmir Blue Sapphires, known for their saturated blue hues. These mines, discovered in the 1880s, produced breath-taking specimens but were depleted in just 5 years, and today, Kashmir Blue Sapphires are among the most coveted and valued gemstones in the world.
Where are Gemstones Found?
Although natural gemstone deposits are found across the world, some regions are particularly renowned for their abundance of high-quality gemstones. From diamonds in Africa to the sapphires of Sri Lanka, and the emeralds of Colombia, some regions have become synonymous with certain types of gemstones.
Sapphires
Sapphires are natural gemstones made of the mineral Corundum. Depending on the trace elements present in the minerals, they can have a range of colours such as yellow, gold, green, lavender, blue, or even multi-coloured (Pitambari).
Although they are found in almost every continent around the world, the most desired and valued sapphire specimens are found in deposits from Sri Lanka (Ceylon), Burma, and Kashmir. Sri Lanka is home to the Ceylon Blue Sapphires, which is famed for its unique cornflower blue shade. Sri Lanka is also an abundant source of yellow sapphires and Padparadscha - a sunset-hued pink and orange gemstone.
Rubies
Rubies are natural gemstones composed of the mineral Corundum - the same as all other sapphires. Their red and pink hues are attributed to Chromium, which is present in trace amounts in the gemstone.
Rubies from the Mogok Valley in Myanmar (Burma) are the most desired rubies in the world. They are highly coveted for their exceptional beauty, scintillation, and unique colour, popularly known as “Pigeon’s Blood”. Owing to political conflicts in Myanmar (Burma) and generally sporadic supply, Mogok rubies are among the most expensive rubies in the world. Despite other mines in Burma, Mogok rubies continue to be coveted by collectors and connoisseurs. Good quality rubies are also found in Madagascar and Mozambique, with the ones from Madagascar known for their pinkish-red tones. Thailand, on the other hand, is a popular origin for glass-filled rubies.
Emeralds
The green variety of the mineral beryl, emeralds are a wonder in themselves. Of every 10 emeralds in the world, 7 are found in Colombia. The country is not only the largest source of emeralds in the world but also produces the highest-quality specimens. The Kagem mine in Zambia is the world's 2nd largest source of high-quality emeralds. The Panjshir Emerald, also called the Afghanistan emerald, is a high-quality emerald found in the Panjshir Valley, Afghanistan. Its unique bluish-green colour ranks it among the finest emeralds in the world. Brazil, too, is an abundant source of emeralds, although these emeralds are generally of lower quality. They are almost opaque and have a large number of inclusions present.
Diamonds
The hardest natural mineral on Earth, diamonds have an appearance unlike any other. For hundreds of years, India was the world’s primary source of diamonds, but today they are mined in over 35 countries across the world. High-quality diamonds are mined in Australia, Botswana, Brazil, China, Congo, Russia and South Africa. Since these are a lot more abundant (relative to coloured gemstones) in various geographies across the globe, their value mostly depends on their quality grade according to the 4Cs, instead of their origin.
Organic Gemstones
Pearls and corals are among the only species of precious stones found underwater, within the seas. They are produced by living organisms and are called organic gemstones. Both pearls and corals are made up of the mineral Calcium Carbonate.
Pearls
Pearls are creamy-white gemstones with an iridescent shimmering sheen (as seen on soap bubbles). The Basra pearls, named after the Iraqi city where they were extensively traded, are one of the most desirable pearl varieties. Because the oysters that produced them are nearly extinct, existing pearls in the market have become much more expensive. South Sea pearls too are a coveted and expensive variety, especially known for their large sizes and symmetry. They are cultured in a saltwater oyster species that is native to the marine waters of the Indian and Pacific Oceans. The golden variety of the South Sea pearls is produced primarily in the Philippines and Indonesia. Pearls are also abundantly found in China but are considered of inferior quality. Keshi pearls are a by-product of pearl cultivation composed entirely of nacre. They are prized for their remarkable lustre and asymmetric shapes. Although earlier cultivated only in Japan and China, Keshi pearls can be farmed in any pearl farm.
Corals (Red & White)
Precious Corals come in 2 variants - red and white. Gemstone-quality red corals are primarily harvested from the western Mediterranean Sea and are sourced from Italy. Japan, too, is a producer of high-quality red corals, and they are valued 3-4 times as Italian red corals. White corals are majorly sourced from Australia, India, Malaysia, Algeria and Africa. White corals from Italy are highly sought-after.
Gemstones Around the World
Gemstones come in all kinds of shapes and colours, and are found in every corner of the world. While it might be impossible to list all of them, some are more recognizable than others. Here's a closer look at gemstone deposits around the world:
Gemstones in Africa
The African continent boasts a wealth of gemstones, with several countries including Kenya, Tanzania, Mozambique, and Madagascar standing out as particularly abundant sources. These precious stones include rubies, sapphires, chrysoberyl cat's eyes, citrines, aquamarines, zircons, and quartz. Zambia is a major global supplier of amethyst. Mozambique is a recently discovered but highly promising source of top-quality rubies. Madagascar has been producing both treated and untreated rubies and sapphires of exceptional quality. Additionally, some recent discoveries have uncovered new sources of high-quality sapphires in East Africa.Gemstones in Australia
Australia is home to the world's highest-quality opals; its opal fields are larger than those found in the rest of the world combined. Many varieties of opal are spread across the continent. Among all the varieties, black opals from Lightning Ridge in New South Wales and white opals from Southern Australia are especially well-known; the former for their rarity and the latter for their rainbow shimmer and play of colour. Other than opals, Australia is also home to varieties of parti-coloured and teal-coloured sapphires.
Gemstones in Asia
The largest of the continents, Asia features a diverse variety of gem-quality minerals. Russia’s Ural Mountains are a significant source of high-quality emeralds and citrines, while peridot is found across Asia – particularly Pakistan and China. Thailand is a popular source of yellow sapphires and rubies, but these are often highly-treated. Along with mines for precious gemstones, India, Sri Lanka, China, Pakistan, and Afghanistan have several rich semi-precious gemstone sources. Sri Lanka is said to be awash with garnets, zircons, tourmalines, topaz and quartz, and India has rich mines that produce moonstones, aquamarines, and star rubies.
Gemstones in the Americas
Brazil, in South America, is home to a spectrum of colourful gemstones including tourmaline, amethyst, topaz, aquamarine, quartz, and emeralds. Chile is a top producer of the beautiful blue lapis lazuli. USA has notable sources of diamonds, opals, quartz, and sapphires – but these are usually a lot more expensive and relatively of lower quality due to expensive labour and production facilities.
How to Choose a Gemstone?
When it comes to diamonds, the most important thing to consider is their grade according to the 4Cs. But for a coloured gemstone, in addition to the 4Cs, its origin can significantly affect its value. Certain origins are known to produce higher-quality gems than others, and similar-looking gemstones found in different locations will almost always have different characteristics and value premiums. It is also worth keeping in mind that rarity does not always equate to superior quality.
When looking to purchase a coloured gemstone, one should always consider the origin of the stone in conjunction with its quality grading. Finding a quality gemstone that aligns with your budget and tastes, may need you to compromise on one or the other factor. When buying a gemstone, all that ultimately matters is how it makes you feel – and at Precious Earth, we firmly believe that there’s no such thing as a perfect gem, but there certainly is one that is perfect for you.
