Final answer:
North Carolina was the leading producer of gold in the United States before the 1850s when the California Gold Rush began.
Step-by-step explanation:
The state that produced the most gold before 1850 was North Carolina. According to the passage, North Carolina was the leading producer of gold in the United States until the 1850s when the California Gold Rush began. In 1799, a twelve-year-old boy named Conrad Reed discovered the first gold in the United States on his family's farm in North Carolina. This led to the establishment of nearly 100 gold mines in the region, and North Carolina produced the most gold in the country until the California gold rush began in the 1850s. It is noted that in 1837, the U.S. government even established a mint in Charlotte to process the gold from this region.