Gemstones are some of the most precious items that we buy. We give them for birthdays, holidays, and even proposals. But where do these colorful stones come from? Before you can consider where gemstones can be found, you must first examine where and how they’re formed.
Most gemstones form below the Earth’s surface. Diamonds and peridot form the lowest of all the gemstones, coming into existence around 125 miles below the earth’s surface. Other, more common, gemstones typically form around 3-25 miles below earths surface. There are three kinds of rock in the Earth, and each of these rock types create different types of gemstones.
Rock Types That Create Gemstones
The first type of rock, igneous rock, forms gemstones in the quartz family (these include amethyst, ametrine, citrine). Other stones found in this type of rock are garnets, moonstones, diamonds, topaz and zircon. The second type of rock, sedimentary rock, is where gemstones such as jasper, malachite, zircon and opal originate. Finally, the third variety, metamorphic rock, gives rise to jade, lapis lazuli, turquoise, zircon, and sapphire. As you can see, zircon can be found in all three types of rock.
Gemstones are created in these types of rocks through several different processes. Some gemstones are created where magma meets rock. As it cools and moves up towards the earth’s surface, it crystallizes. If the lava doesn’t make it to the surface, it will form coarse minerals that will turn into the gemstones people are looking for. Other gemstones are created through pressure in different layers of the earth, which fold over and back onto themselves, crushing the minerals in just the right way to create gemstones deep below the earth’s surface. Gemstones get closer to the surface of the earth through earthquakes, plate shifts, and other natural processes. When gemstones are close enough to the surface they can be mined.
Mining For Gemstones
The mining of gemstones is a process that involves heavy machinery. Diamonds are harvested from pits. This harvesting includes trucks, hydraulic shovels and heavy machinery to retrieve diamonds. Diamonds typically cluster together in large groups that can be continually mined for an extended period of time. Other gemstones are different. Colored gemstones cannot be mined in large quantities, as they do not cluster in the same way. Colored gemstones occur sparsely in the rocks they are found in. This means that one large rock may only have a few gemstones, and they do not cluster next to each other. This makes colored gemstones more difficult to find and uncover, and therefore do not garner the attention of larger mining companies. This means that colored gemstones are often mined by smaller, independent miners who use the manual methods that we think of when someone mentions mining.
The final way colored gemstones may be recovered is in alluvial deposits. Sometimes gems are worked to the surface of the earth due to erosion. When these gems find themselves in water they re smoother, rolled around, and tossed in the waves of the ocean. This results in rounded gems. Their hard edges have been smoothed and rounded, resulting in more regularly shaped gemstones.
Gemstones From Australia
Australia produces a large array of different gemstones. most are igneous gemstones so they are darker in color. Opal is of course the most famous gemstone found in Australia. Read our complete list of Australian gemstones here.
Gemstones From The USA
Did you know the USA actually produces some very beautiful gemstones? Aquamarine, Red Beryl and of course Montana Sapphire or Oregon Sunstone. Read about the full list of American gemstones here.
Gemstones From South America
South America is a hot spot for gemstones because of the hydrothermal activity that has occurred in the region. Check out our full list of gemstones found in South America here.
With all of these different processes of creation, gemstones can be found almost anywhere. Diamonds are often found clustered below the surface. Colored gemstones can be found near the surface and sparsely spread. Finally, exposed gemstones can be found in deposits where they have been dropped and smoothed by river and ocean waters.