What might a 1 carat mine cut diamond at least from 1865 be worth?

The value of a 1-carat mine-cut diamond from 1865 can vary significantly based on factors such as clarity, color, and overall quality. Generally, antique diamonds like these can fetch prices ranging from $3,000 to $10,000 or more, depending on their unique characteristics and market demand. Additionally, the historical significance and the craftsmanship of the cut can further influence its value. It's advisable to have the diamond appraised by a certified gemologist for an accurate valuation.