The Disk of returning was used to let players exit the Black Hole in RuneScape Classic. At the time, a non-player character called Thordur sold them for 10 coins. This item is the second oldest rare or discontinued item in the game, beating out the pumpkin as this disk was created back in July 2001. The oldest rare is the half full wine jug, being released on the first day of RuneScape. This item was discontinued December 2001 after the removal of Thordur and the Black Hole. Due to their rarity, trade volume is very low on the Grand Exchange which does not allow their market price to update often. As a result, Disks of returning's Street value differs greatly from their Grand Exchange value.
People that were banned were put into a hole and trapped there until their ban was over. A lot of people got themselves banned just to see the hole, so Jagex made a mock hole and created a disk to let players out once they went in. To get out of the Black Hole, players would select the spin option on the Disk.
The mock black hole was removed and the disk of returning became discontinued because of a scam that involved convincing players to drop their disk while in the black hole, which trapped them until they were assisted by Jagex. The remaining disks were left in the game, but no longer had any use.