From the category archives:

Gemstone Mines

The Williamson Diamond Mine

by gesner12 on December 30, 2011

The Mogak Burma Ruby Mines

by gesner12 on December 15, 2011

History of Columbian Emerald Mines

by gesner12 on December 15, 2011

The History of Kashmir Sapphire Mines

by gesner12 on December 15, 2011