Precious gemstones include diamonds and colored stones such as gemstones, emeralds and sapphires. Although diamonds remain the most expensive gemstone, colored gems are rapidly gaining popularity.
Diamonds and peridot, are found much deeper in the earth. Diamond forms in “kimberlite pipes” that originate in the earth’s mantle (>125 miles) and end at the surface. Molten magma running through these pipes usually reaches the surface as lava and cools off, but if it doesn’t reach the surface, it cools more slowly, crystallizes, and forms coarse-grained minerals.
The first type of rock, igneous rock, is formed by cooling and crystallization magma beneath the earth’s surface, or as the lava flows under the surface of the interconnected strata, which grows in the aggressive igneous rock, while the existing elements, cooling time and gemstones can be made based on the environment.
Gemstones in the igneous rocks include quartzes, amethyst, citrine, ametrine, garnets, moonstone, apatite, diamond, spinel, tanzanite, tourmaline, topaz and zircon. Some of these gemstones form in pegmatite and hydrothermal veins that are genetically related to igneous rocks.
Sedimentary rock is the second type and produces transported minerals such as jasper, malachite, opal and zircon. Sedimentary rocks are formed when rock is worn down and the fragments are carried by water or the wind, and they are finally compressed together over time.
The third type, metallic rock, is formed when intense ground heat or pressure changes rocks. The beryls, emerald, morganite, aquamarine, jade, lapis lazuli, turquoise, spinel, ruby, sapphire and zircon are formed in metamorphic rock.