One of the most interesting souvenirs you can buy in Udaipur is a miniature painting. These were historically used to document the life of royalty.
They are crafted with a paintbrush using a single camel eyelash hair. This allows extremely fine control and minute detail. The paint used is made from materials like graphite, lapis lazuli, gold, silver, and concentrated camel urine. They are painted on a variety of substrates ranging from silk to bone to canvas.
When we visited Udaipur we toured a miniature painting gallery. The techniques used in crafting these paintings were demonstrated. And, of course, we were given the opportunity to purchase one to take home with us (which I did).