Recognition and dogged pursuit of economic opportunities throughout southern Arizona during decades spanning the turn of the 20th century provided the stable foundation for later growth and prosperity. The story of the Silver Bell mining district exemplifies the role copper mining played in the area's rich history. Over the past 150 years, the Silver Bell mining district evolved from a collection of small, intermittent, poorly financed and managed underground mining operations that struggled to make a profit from high-grade ores; to a small but profitable producer, deploying innovative mining practices and advancements in technology to successfully develop the district's large, low-grade copper resource.