Iranian Rial and its worth

I think the Rial originally was the Spanish Real made from Mexican silver, which was the currency accepted all over the world in the 16th Century.  

Each silver real weighed 3.433 grams at a fineness of 93.1% silver. Today's silver price (March 23, 2026): $70.78 per troy ounce (31.1035 g). One Spanish real would be equivalent to $7.28 USD. Ten Million Iranian Rials would be worth... not much.