Yf ten thousand feet of silver means that the silver content reaches more than 999.9‰. Yf is the abbreviation of brand name or brand name, and 999.9‰ is silver, which is also a relatively empty concept.

AU stands for gold. If there is gold on the ring, the former YF is the symbol of the ring processing unit. For example, Cuihua's gold products include CH+ gold (pure gold, thousands of gold).