Bible Dictionaries
Pietra Dura

Webster's Dictionary

Hard and fine stones in general, such as are used for inlay and the like, as distinguished from the softer stones used in building; thus, a Florentine mosaic is a familiar instance of work in pietra dura, though the ground may be soft marble.

Bibliography Information
Webster, Noah. Entry for 'Pietra Dura'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​p/pietra-dura.html. 1828.