Step one is to have the ore tested by Assay. This will tell you if there is actually gold in the ore. What you have is quartz, one of the most common minerals on planet earth because it is formed of the two most common elements in the earth's crust: Silicon and oxygen. There are many, many quartz veins with very little or no gold. Even in a vein which does have gold in some parts of it, there are often portions of the same vein which are barren and have very little or no gold. If an assay shows little gold, there is no point in going farther - its time to quit.
This type of ore is not a concentrate, it is a raw ore. It must first be crushed to powder to extract the gold. Rock crushing equipment will cost many thousands of dollars even if you purchase small scale crushing equipment from China - At least US $5,000 and more likely closer to US$ 10,000. Although a variety of treatments to extract gold exist, unless you have loads of money to invest (perhaps something closer to US $100,000) - your best bet is to investigate the potential for treating the ore by gravity based methods (gravity methods means the use of gold's high density to separate it from low density materials like quartz). It is the most economic type of plant to set up, the most common for small operators and the easiest to operate. However, not all ores are successfully treated by gravity methods. You must test the ore to see if gravity methods will work on this ore.
Often there are operators who set up ore processing plants in the gold bearing regions of Africa to process the local ores mined there. They process the ores produced by the miners for a fee. This is a far better business model than the miner selling you ore. If he sells you barren ore, you will process it and get little or no gold - but the loss of money will be yours. If the miners pay a fee to have their ore processed then the responsibility of delivering rich ore to the processing mill is on them - so that if the ore is barren the miner takes the loss. You might consider traveling to the region where the ore is produced and see if these mills exist and see what methods they use to treat the ores. It will likely be a gravity based method, but there are a variety of ways of crushing ores and a variety of ways to process the ore using gravity. I am sure you would find it a worthwhile education.