Today, on Blue Nile, you can purchase a diamond weighing one carat and pay between US$2,007 and US$17,760, depending on the cut, clarity and colour that you want to pay for.
This answer assumes that your notation indicates a D colour, and an Internally Flawless clarity. In a random search for the size, colour and IF designation, these prices appear current as of December...
As a rough stone, there is no fixed price for a diamond, because its clarity, its colour, and its cut are not determined. Take your rough stone to a diamond cutter who can plan a cut for the stone....
The range of quality for diamonds is so broad that you could charge from US$1.20 per pound -- if you're selling industrial diamonds in bulk with a long-term, regular-delivery contract, to millions...
Uncut diamonds that come from within the earth can have rough edges. Sometimes they are called 'rough' diamonds: more commonly raw diamonds, because they have not been cut and polished into gemstones.