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.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). pietra dura. Retrieved September 26, 2026, from http://smartdefine.org/pietra_dura/definitions/2045442 |
| Chicago | Webster's. 2011. "pietra dura" http://smartdefine.org/pietra_dura/definitions/2045442 (accessed September 26, 2026). |
| Harvard | Webster's 2011, pietra dura, Smart Define, viewed 26 September, 2026, <http://smartdefine.org/pietra_dura/definitions/2045442>. |
| MLA | Webster's. "pietra dura" 27 May 2011. Web. 26 September 2026. <http://smartdefine.org/pietra_dura/definitions/2045442> |