The 1802 Mohur was minted in Bombay in the name of Shah 'Alam II, the 18th Mughal Emperor. It carried an extremely rare privy mark which meant it was one of only two recorded examples to have emerged at auction - the other made $5000 () in New York in 2008.
In fine condition, it overshot a £2500-3000 estimate and sold at £13,000.
The auction was a timed online-only sale which closed on April 13.
Also at the sale, a rare Dinar from the reign of the last Abbasid Caliph in Baghdad, Al-Musta'sim Billah but with no mintname went over a £2000-2500 estimate and sold at £7550.
From the year 655h (1257?), the coin was believed to be the only known example of a fourth period Abbasid dinar without a mintname. The auctioneers said it may have been struck by a travelling army mint during the campaign against the invading Mongols.
Overall, 212 of the 258 lots offered sold (82% sold by volume) for a hammer total of £111,716. This exceeded the sale's low-estimate of £103,490.
Matt Curtis of Wilkes & Curtis said: "These high prices prove that customers are confident buying from us with our online-only format. As our customers have grown with us they have really got the feel for timed auctions. This is definitely the future for coin auctions.
"Despite being a timed online auction the bidders were still 'present' on the day as shown by the fact that the total bids received increased by 30% in the last few hours."
Wilkes & Curtis' next auction will close on June 15. The Consignment deadline is May 5.
The buyer's premium at Wilkes & Curtis is 10%.