Braidenium is a special element - One that can turn into any other like magic once enough is included - A mimica. (Iron + Braidenium = Iron-like substance, Hydrogen + Braidenium = Hydrogen-like substance, etc.) If not enough let it transform into a mimica, then Braidenium is a transparent gas which can only be seen properly with infared light. Braidenium on powers of two are the most stable*, and stability decreases with size of isotope or amount. The reason the whole Mimicing thing exists is thanks to Braidenions, which are a special type of neutrino-Positron that can energise neutrons into mimicing into other elements. The nuclear mass of a single Braidenium is about 300, and each Braidenion added adds the logarithm of the amount of Braidenions in the nuclear mass. (2 Braidenions = 300 + Log(2) = 300.30103...) Since this would be pretty hard to document, I use the number of Braidenions as the Isotope number instead.
Zoom in to see the third one