Thailand (formerly the Kingdom of Siam) is a major worldwide gem trading, gem processing and gem treating center, with the cities of Chanthaburi and Bangkok at its hub. Thailand's gem and jewelry exports are expected to reach $4.75 billion US in 2008 [6]. Known primarily for its ruby and sapphire, there are several other notable gemstones that are mined in Thailand, such as amethyst, aquamarine, garnet, spinel, and zircon.