Selling ancient coins in India can be a profitable business if one does the groundwork properly and knows what he wants to deal with. First, it is necessary to check out if the coins have value or no. But their value is largely derived from the rarity, age, condition, and historical significance. Consulting a numismatist or coin specialist or researching your collection on auction sites and coin forums — you can find eBay links and other sources in a sidebar of the article — can help you estimate what your coins are worth.

After judging the approximate value, there are a few ways to sell old coins in India. The time-honored method is through coin dealers or antique shops where you can receive an immediate appraisal and purchase offer.
That said, this may not always get you the best price as dealers often want to put some meat on the bone. You could also consign them to an auction house, offline or online, which is esp nice for rare/valuable coins as you can have a bigger audience and attract higher bids.
Platforms like OLX, eBay, or coin marketplaces make it quick and easy to list your coins for sale. Yet buying directly from online channels has a danger of scamming buyers and potentially carries implications. Always check the credibility of the buyer and use secure payment options.
Also, coin exhibits and shows are great ways for enthusiasts to get acquainted with other enthusiasts during their leisure hours. Now this is an opportunity that showcase your collection in front of buyers who care about the products.