According to Wikipedia, the region of Tamil Nadu in southern India was ruled by four medieval dynasties. The Chola Dynasty gained superiority in the time frame around 1000AD. The coins in our pictures show the leader of the Chola Dynasty, Rajaraja Chola I.
It is pretty exciting times for numismatics (coin collecting) as heretofore quiet nations emerge onto the world stage. Notably coins from India and China are gaining plenty of attention, and these coins from Southern India and Sri Lanka are no exception. You are starting to see these coins appear on eBay and other auction sites, as well as a few 'coin-talk' discussion forums, like this one. Coins from India are pretty much absent from the US numismatic press and the big-time global auction houses, but Chinese coins are presenting themselves more and more. A notable exception for Indian coins is this beautiful Chola piece on the Classical Numismatic Group web site.
As with all emerging markets, there is only sketchy information available. This information also changes rapidly with time. As best we can tell here at CoinQuest, these Rajaraja pieces come in a few different patterns and in three different metals: copper, silver, and gold. The one in our primary picture is made of copper, and has eye appeal much better than you usually see. The inscription is in Devanagari and reads 'Sri Raja Raja'. The denominations are known variously as 'massa', 'kasu' and 'kahavanu'.
The primary problem with evaluating such coins is counterfeiting. It does not take much modern technology to mimic the coinage of 1000AD. Counterfeits are rampant in coins from ancient Greek, Roman, and Byzantine empires and there may (or may not) be plenty of counterfeits in old Indian coins. It is not clear how to authenticate an old coin from the Chola Dynasty. If a reliable authentication service arose, I am sure it would do well.
Here are CoinQuest's best guess at catalog value for these pieces. These values apply only to genuine coins. Counterfeits are worth zero.
worn (like our picture): $5 US dollars
well preserved: $20
worn: $15 US dollars
well preserved (like our picture): $300
worn: $200 US dollars
well preserved (like our picture): $400
These are approximate catalog values. Use our Important Terminology page to convert them to actual buy and sell values.
CoinQuest thanks Oesho (figleaf) on WorldofCoins.eu for use of the silver and gold coin images. They are beauties!