noun
fineness of gold; gold purity
Technical term used in metallurgy, jewelry, and assaying to indicate the proportion of pure gold in an alloy, often expressed in karats or parts per thousand.
この指輪の金位は18金です。
The fineness of this ring is 18 karat.
金位を調べるために試金石を使う。
Use a touchstone to test the purity of gold.