Book 2 Chapter XII Paragraph 22

The superintendent of mint (lakshnádhyakshah), shall carry on the manufacture of silver coins (rúpyarúpa) made up of four parts of copper and one-sixteenth part (másha) of any one of the metals, tikshna, trapu, sisa, and anjana. There shall be a pana, half a pana, a quarter and one-eighth.