I want to introduce just Iranian crystals in this topic.First, let's take a look at the history of mine in Iran.
Iran has been the pioneer of mining exploration and techniques for several millennia. The knowledge and talent of primeval Iranians on one hand and high potential of mineral deposits, their diversity and absence of dense vegetation cover on the other hand, as well as the country’s position at the crossing of various cultures and civilizations, have led to prosperous mining activities in ancient times and even after the renaissance, which still amaze the mining engineers about the Iranian expertise in mining.
Hundreds of primordial mining sites of gold, copper, iron, lead and zinc, and silver have been discovered that indicate centuries of mineral excavation. Numerous mining localities, tools, smelters, and miners’ residence existed since fourth millennium B.C. (ref : The Economic Geology of Iran , book, Author: Mansour Ghorbani)
Iran with roughly 1% of the world's population holds more than 7% of the world's total mineral reserves.(ref: wikipedia).
If these entries were not enough, you can get more information on the Internet.