Touchstone

1.

(a stone formerly used to test the purity of gold or silver, a standard or criterion by which something is judged) jeweler's touchstone ថ្មដែលគេយកមកសាកមើលមាស (ថាសុទ្ធមិនសុទ្ធ), touchstone of its genre គំរូ

1.

Lydian stone; basanite; -- so called because used to test the purity of gold and silver by the streak which is left upon the stone when it is rubbed by the metal.

2.

Any test or criterion by which the qualities of a thing are tried.