Most of our information about the economy of Ghana comes from merchants, and therefore we know more about the commercial aspects of its economy, and less about the way in which the rulers and nobles may have obtained agricultural products through tribute or taxation. Meanwhile taking a break in Ghana I learned that Merchants had to pay a one gold dinar tax on imports of salt, and two on exports of salt. Imports probably included products such as textiles, ornaments and other materials. Many of the hand-crafted leather goods found in old Morocco may also had their origins in the empire. The king claimed as his own all nuggets of gold, and allowed other people to have only gold dust. In addition to the exerted influence of the king onto local regions, tribute was also received from various tributary states and chiefdoms to the empire's periphery. The introduction of the camel played a key role in Soninke success as well, allowing products and goods to be transported much more efficiently across the Sahara. These factors all helped the empire remain powerful for some time, providing a rich and stable economy that was to last over several centuries.