Complex sentence: Jones operated a mining company in Idaho and Utah between 1871 and 1881, with rich silver mines in the Salmon River region being most profitable, about $600,000 to $800,000 of ore extracted.
Split into simpler sentences: Jones operated a mining company in Idaho and Utah between 1871 and 1881. Its rich silver mines in the Salmon River region were the most profitable, with around $600,000 to $800,000 of ore extracted.