Why are Opals mainly located in Australia? This valuable gem is mainly located Down Under. For that reason, Australia is the World Heavyweight Champion in opal production. Its nearest challenger is Mexico with minor percentage of production. In fact, almost 95% of opals come from Australia which means that the share of all other countries, such as Mexico, Brazil, Czech Republic and some parts of United States of America, in the world’s opal market supply in less than 5%. The most famous opal locations in Australia are Lightning Ridge, Coober Pedy, Andamooka, White Cliffs, and Cunnamulla dis...