At the time, White Cliffs was the opal capital of NSW, and its rough stones were sent to Germany to be cut and polished. Soon after, gem cutters started to arrive at the opal fields, although many miners still cut their own opal, often very roughly.
Circa 1915 marks the beginning of an opal fever in Coober Pedy, back then a no-name location which soon became known as the Stuart Range Opal Field. It is said the opal to start the opal rush was found by a teenage boy, William Hutchison, who was a part of a gold-prospecting group. Although the first opal claim was staked soon after, the area did not become the flourishing Opal Capital right away; soldiers returning from WWI would come to town to try their luck with mining but the real opal boom did not occur until post-WWII. The economic depression of the 1930s crippled the opal production, although this was the time when opal was discovered in Andamooka, and later Mintabie. Because of the quality of the opal emerging from Australia, the European opal mines were forced into shutdown in the 1930s, unable to compete. Australian opal mines then became the primary and most respected opal producers, largely due to the variety and quality of the opal they produced.
The economic depression, followed by WWII prevented the opal mining industry from blossoming until late 1940s-1960s when many Europeans fled their devastated homelands in favour of the remote Australian opal towns and turned their eyes to opals.
The mining of boulder opal was also significantly impacted by the two world wars and did not gain recognition until 1967, when Des Burton, a pharmacist from Quilpie, developed open cut mining techniques which contributed to revolutionising the boulder opal mining industry over the 1970s.