On 7 September 2014, the price that a Mages' book could be bought on the Grand Exchange fell sharply from around 500,000 to around 30,000. The cause was never officially been stated. Mod Tyran stated that it was not caused by an in-game glitch or item duplication. On 8 September 2014, excess Mages' books were removed from players that had purchased bulk amounts of them in the previous 24 hours, without refund.