The Indian Rupee coins are available in denominations of ₹1, ₹2, ₹5, ₹10, ₹20,₹25, ₹50, ₹100, ₹500 and ₹1000. The coins for ₹20 and above are for commemorative purposes only.

Commemorative coins are coins that were issued to commemorate some particular event or issue.Indian commemorative coins were issued from the 1964s onwards. Such coins have a distinct design with reference to the occasion on which they were issued. Many coins of this category serve as collectors items only, although some are also issuing commemorative coins for regular circulation.Commemorative coins are made at various mints across India including the ones at Mumbai, Noida, Calcutta & Hyderabad.

The highest value coin is ₹1000 issued on the occasion of 1000 years of Brihadeeswarar Temple.

Source: http://en.wikipedia.org/wiki/Commemorative_coins_of_India