In Rubaya one kg of manganese sand is sold for 10 dollars per kg. In Goma, the same can be sold for 70 dollars. Over the border, in Rwanda, the price can reach 105 dollars per kilo, and this is the price for the rough, unrefined product. Rwandan officers are able to get great quantities of the mineral across the border, but clandestine passages through the forest and aircraft have also been used. From 25 kg of rough minerals you get 1 kg of end product. The value is about 500 dollars per kg if it's coltan.