The Gulf countries are countries which are located in the area surrounding the Persian Gulf. They form a part of the subcontinent known as the Middle East, to distinguish from the countries in the far East of Asia like Japan, China, Taiwan. All of the Arab states of the Persian Gulf have significant revenues from oil and gas. Gulf countries together cater one third of the worlds fuel requirements. The chief supports of the economy in Gulf countries are furnished by oil resources but the countries are trying to diversify its earnings. In the Middle East, Bahrain has earned the rank of being the most economically progressive country and it is known worldwide as the 16th most free economy (ranked by The Heritage Foundation). Regional tourism is also a significant source of income. In the Gulf region Israeli diamond cutting industry is one of world's major centers in cutting and polishing of the precious stone. While Kuwait Economy is free and open by its nature and is one of the most prosperous economies in the world. Iran has the world's largest zinc reserves and second-largest reserves of copper.