The correct option is Agate.
Explanation
Mughal miniature painting was a highly intricate art form involving a multi-stage process. This included the preparation of paper (Wasli), sketching, the application of pigments, and a crucial finishing technique known as burnishing to ensure the longevity and luster of the artwork.Detailed Analysis:
After the application of colours, the painting required a process to set the pigments firmly into the paper fibers and to create a smooth, glossy surface. This was achieved through burnishing.
- The tool used for this purpose was a smooth, rounded stone made of Agate (often referred to as Aqiq).
- The painting was placed face down on a smooth stone slab, or the burnishing was applied directly to the painted surface, depending on the stage of the work.
- Rubbing the agate stone over the painting compacted the pigments and the paper, giving the miniature its characteristic enamel-like finish and sheen.
Key Takeaway:
Agate is the specific gemstone used in the burnishing process of Mughal paintings to set colours and provide a uniform, glossy texture.