Touchstone

Touchstone is a tool or method used to evaluate and compare the quality, authenticity, or value of something, such as materials, ideas, or products. Historically, it referred to a stone used to test the purity of metals like gold by observing how they reacted to the stone. In broader use, a touchstone serves as a standard or benchmark to assess whether something meets certain criteria or standards. It helps ensure consistency, quality, or integrity by providing an objective reference point for evaluation.