It's highly unlikely. Ioun Stones (in D&D) date from at least as early as 1979, in the original Advanced Dungeons & Dragons Dungeon Master's Guide, while the first of the second set of Amber novels, Trumps of Doom, featuring Merlin didn't come out until 1985.

Ioun Stones: There are 14 sorts of useful ioun stones. These magical stones always float in the air and must be within 3' of their owner to be efficacious. The new possessor of the stones must hold each and then release it, so it takes up a circling orbit, whirling and trailing, circling at 1' to 3' radius of his or her head. Thereafter, they must be grasped or netted to separate them from their owner. The owner may voluntarily seize and stow the stones (at night, for example) to keep them safe. He or she would of course lose the benefits during that time.

It's highly unlikely. Ioun Stones (in D&D) date from at least as early as 1979, in the original Advanced Dungeons & Dragons Dungeon Master's Guide, while the first of the second set of Amber novels, Trumps of Doom, featuring Merlin didn't come out until 1985.

Ioun Stones: There are 14 sorts of useful ioun stones. These magical stones always float in the air and must be within 3' of their owner to be efficacious. The new possessor of the stones must hold each and then release it, so it takes up a circling orbit, whirling and trailing, circling at 1' to 3' radius of his or her head. Thereafter, they must be grasped or netted to separate them from their owner. The owner may voluntarily seize and stow the stones (at night, for example) to keep them safe. He or she would of course lose the benefits during that time.

It's highly unlikely. Ioun Stones (in D&D) date from at least as early as 1979, in the original Advanced Dungeons & Dragons Dungeon Master's Guide, while the first of the second set of Amber novels, Trumps of Doom, featuring Merlin didn't come out until 1985.

It's highly unlikely. Ioun Stones (in D&D) date from at least as early as 1979, in the original Advanced Dungeons & Dragons Dungeon Master's Guide, while the first of the second set of Amber novels, Trumps of Doom, featuring Merlin didn't come out until 1985.

Ioun Stones: There are 14 sorts of useful ioun stones. These magical stones always float in the air and must be within 3' of their owner to be efficacious. The new possessor of the stones must hold each and then release it, so it takes up a circling orbit, whirling and trailing, circling at 1' to 3' radius of his or her head. Thereafter, they must be grasped or netted to separate them from their owner. The owner may voluntarily seize and stow the stones (at night, for example) to keep them safe. He or she would of course lose the benefits during that time.