The 39 Clues Wiki
The 39 Clues Wiki

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Mercury is an Ekaterina Clue and is part of Gideon Cahill's master serum.



The Mercury Symbol

The true reason of the fight between the two legendary inventors Thomas Edison and Nikola Tesla was because they were both Ekaterinas looking for one of their branch's lost Clues, and their competitive nature got the best of them. One of them (Nikola Tesla) had a breakthrough, so he hid the Clue in his secret lab in Croatia.

Card Combo[]

This Clue can be unlocked in Mission 6: The Mad Scientist's Clue or by completing the following card combo:

Card81 Card98 Card100 Card106 Card119


Mercury was usually used in thermometers, but now it isn't used because it is highly poisonous and may cause death. This element is one of the two elements that are liquid at room temperature, along with bromine. It has the atomic number of 80.


A Cup Of Mercury


The cutscene shows Nikola Tesla's Croatian home. Two bulbs on the left and right side start to build up electricity until blue light flies outwards from them. The screen flashes to the word 'MERCURY' and the branch crest, and then they fade.

614 - Metal Tattoo - Texture

Mercury design