'Irish touchstone' definitions:

Definition of 'Irish touchstone'

From: GCIDE
  • Touchstone \Touch"stone`\, n.
  • 1. (Min.) 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. See Basanite. [1913 Webster]
  • 2. Fig.: Any test or criterion by which the qualities of a thing are tried. --Hooker. [1913 Webster]
  • The foregoing doctrine affords us also a touchstone for the trial of spirits. --South. [1913 Webster]
  • Irish touchstone (Min.), basalt, the stone which composes the Giant's Causeway. [1913 Webster]