With reference to medieval Indian architecture style, what is ‘Pietra Dura’?

Explanation

Pietra Dura is an Italian term meaning “hard stone.” In the context of medieval Indian architecture, it refers to the technique of inlaying semi-precious stones (like agate, jasper, coral and lapis lazuli) into marble or other stone surfaces to create intricate and colourful floral or geometric designs. This technique was famously used in the decoration of the Taj Mahal.