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This article is associated with The Maze of Bones

Iron Solute is one of the 39 Clues that make up Gideon Cahill's master serum. To unlock this clue, one must add the 6 cards from The Maze of Bones.


Amy and Dan Cahill discovered that the piece of paper Grace Cahill gave them has the Clue after all. RESOLUTION was the answer to the missing word. Dan solved the anagram, discovering the clue IRON SOLUTE.


The Cutscene shows exactly the same paper that was given to Dan and Amy.The letters in the RESOLUTION go out and go in another place and forms the word Iron Solute.


The key on the cards that form the card combo for this Clue contains a bone.

Card Combo

Card1 Card2 Card3 Card4 Card5 Card6

About Iron Solute

Iron solute is used for many things. It can be used for metalworking and chemistry.

The formula for iron solute is Aluminum Alloy Solution (AAs).


  • In the book, Amy says it is an ingredient for ink.
  • "Solute" means "dissolved in water" so "Iron solute" can be written Fe (aq).
  • Grace Cahill wrote RESOLUTION as an anagram to it.

    The Iron Solute Symbol

Iron Ore

Iron before it is liquified into Iron Solute

The 39 Clues Clue 18

The 39 Clues Clue 18

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