Topaz also belongs to a silicate mineral class of aluminum and fluorine, which crystalizes in the orthorhombic system. Its crystals are predominantly prismatic, completed by pyramidal facets. This stone is ranked among the hardest naturally-occurring gemstones in the world and is the hardest of all silicate minerals.
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It is also one of the most preferred stones for manufacturing expensive jewelry due to its hardness and clarity. In its natural state, Topaz is golden brown, although at times it can be yellow. It is commonly found in Nigeria and is currently selling at $300 per carat.
If gold and diamonds aren’t your thing, then you should consider one of these rare gems from interior parts of Africa.