22. A number of our people have narrated from Ahmad ibn Muhammad from al-FIusayn ibn Sa‘id from ‘Abd Allah ibn Yahya from ibn Muskan from abu ‘Abd Allah, Mawla “Abd Rabbihi who has said the following: “This is concerning my question before abu ‘Abd Allah , about the case of a substance that was taken from the mine in which there were gold, silver and zinc. How could we buy it? He (the Imam) said, ‘You can buy it with both gold and silver.’”