Mining is the second step in the diamond commodity chain. After the diamonds have been located within the rock they need to be extracted. The extraction can be done in a few ways. One is open pit mining. This is where diamonds are found on the surface of the ground. Another way is underground mining. This is where diamonds are extracted from below the ground surface. Underground mining can occur at depths over 1km under ground. Coastal and inland mining is another common practice. This is where sand and soil is removed to find diamonds. Similarly there is marine mining, which is where diamond extraction occurs on the seabed. Extraction is only the first step in the mining process.
After extraction the ore containing the diamonds needs to go through a sequence of crushing and processing in order to obtain rough diamonds. After this process only 20% of diamonds are found to be suitable for the gem market.