how did it effect the world economy?
It stimulated economies around the world.
California Gold Rush
The Gold Rush stimulated economies around the world as well. 
someone who went to california during the gold rush Forty-niners. when did it take place? 1848. who was the first person to discover it? James W. Marshall. how many took part in it? The news of gold brought approximately 300,000 people to California from the rest of the United States and abroad. what was it's impact? The human and environmental costs of the Gold Rush were substantial. Native Americans, dependent on traditional hunting, gathering and agriculture, became the victims of starvation and disease, as gravel, silt and toxic chemicals from prospecting operations killed fish and destroyed habitats.
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California Gold Rush [SEP] World-wide economic stimulation
The Gold Rush stimulated economies around the world as well. Farmers in Chile, Australia, and Hawaii found a huge new market for their food; British manufactured goods were in high demand; clothing and even prefabricated houses arrived from China. The return of large amounts of California gold to pay for these goods raised prices and stimulated investment and the creation of jobs around the world. Australian prospector Edward Hargraves, noting similarities between the geography of California and his home country, returned to Australia to discover gold and spark the Australian gold rushes. Preceding the Gold Rush, the United States was on a bi-metallic standard, but the sudden increase in physical gold supply increased the relative value of physical silver and drove silver money from circulation.