Wow, that is too many geological terms, let me try and explain each one with the help of far more knowledgeable sources so by the end of the article we all know how aquamarine is formed. Over many millions of years continual geological processes transform one type of rock into another. For our discussion we are interested in igneous rock.
Deep in the earth's core there is molten rock magma at extremely high temperatures. During volcanic events this magma is forced to the earth's surface and cools to form igneous rock.
There are many different types of igneous rock depending on the processes and chemicals that form them; one of these is pegmatite. These pockets eventually crystallize to form a special type of rock called a pegmatite. Due to the high water content these crystals can form faster than other crystals, are often flawless and are usually quite large.
BERYL One of the minerals that can occur in these pegmatites is beryl and when certain other elements are present, different types of beryl are formed. The 6 main varieties of beryl are aquamarine blue-green , emerald green , morganite pink , red beryl red , heliodor yellow and maxixe deep blue. See the video of a miner finding an aquamarine crystal in Georgia, you can just imagine a pool of water trapped in the rock in ancient times and slowly forming this beautiful crystal.
They heat up when they interact with magma which forms the gemstone. Pegamites are rocks that are formed during the final stages of magma crystallisation. Almost all aquamarines are formed in pegmatites. Aquamarine can be found in many places around the world where there are mountains.
The quality of aquamarine depends on the color. When the color is richer and deeper it is more valuable. Most have light colored stones and very rare will you find aquamarines with a cat eye effect.
The crystals can be quite large and totally transparent. Aquamarines forms into stunning flawless crystals which can create some beautiful masterpieces. The stones can be heated to a very high temperature so that it can have the beautiful sky blue color. Most gemstones are actually heat treated. You can use aquamarine as jewelry such as rings, earrings, and bracelets which can be made from the beautiful gemstone. The extremely large gemstone that is too big to be formed as a piece of jewelry are faceted for exclusive collectors.
Brazil is a major producer of the gem aquamarine and Pakistan produces the most outstanding crystals of the aquamarine. A dark and deeply saturated blue is the most valuable and most durable of gemstones but still, requires careful handling and care. A different kind of aquamarine caught the eyes of gemstone miners and gem cutters in India over a thousand years ago.
If you held the opaque blue stone at an angle and tipped it to catch the light, a band of light would dance across it. This effect, known as chatoyancy , is one we've explored here before.
But chatoyant aquamarine gets its effect from a different cause than tigers eye. Instead of asbestos fibers, cat's-eye aquamarine is filled with microscopic rods all laid in the same direction. They give these aquamarines a satiny appearance in addition to the cat's-eye band of light, and they're subtly stunning. Chatoyant aquamarine has now been found worldwide, although it's still rare.
If you want to find any in North America, so far your best bet is the granite pegmatites of old New England, where ancient mountain building episodes have left us a legacy of gem-filled granite. The chatoyant aquamarine found in the spoil heaps of old mica mines have reached sizes of nearly 20 carats, and if imperfection doesn't bother you, you can score even larger specimens.
The chatoyancy of aquamarine is usually subtle, but some of the gems here are nearly as intense as the finest cat's-eye chrysoberyl. Even rarer aquamarines exhibit asterism , which you'll be familiar with if you've ever seen a star sapphire.
Pretty nifty for a stone most of us have never thought of as anything but a sparkly clear crystal! In all of its variety, there's still something intensely satisfying about the classic seawater variety of aquamarine. The next time you see one, you can marvel at how such a cool, serene stone emerged from heat and darkness deep under the earth.
Badar, M. International Journal of Economic and Environmental Geology. Biswas, Arun Kumar : Vaidurya, Marakata and other beryl family gem minerals: etymology and traditions in ancient India. Indian Journal of History of Science , 29, 2, Gosse, R.
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