Final answer:
Beryl is a colorless mineral that, when containing Cr3+ impurities, forms emeralds. The global distribution of emerald is often controlled by large companies with vast production and distribution networks, while local distribution varies and can be affected by political and economic factors.
Step-by-step explanation:
The mineral beryl is a crystalline beryllium aluminosilicate with the chemical formula Be3Al2Si6O18. Pure beryl is colorless, but the presence of impurities can lead to the development of colorful gemstones. For instance, when 1% of the Al3+ ions in beryl are replaced by Cr3+ ions, the mineral takes on a green hue and is known as emerald.
Gem beryl, including emerald, is distributed both globally and locally. Global production is typically dominated by large companies that manage the mining, production, and distribution of these gemstones. An example of this would be DeBeers, which controls a significant portion of the global diamond market. These large companies have an extensive network and influence, despite facing growing competition.
Local distribution of gems like emeralds can vary significantly. In regions such as Burma, precious gemstones such as rubies, sapphires, and jade are found in abundance. However, the income generated largely benefits the local military rulers, leading to limited economic development for the populace and discouraging foreign investment. Similar local distribution patterns are observed in other gem-producing regions, where political and economic factors heavily influence the availability and sale of these precious stones.