Native SIENNA exists as a SNIP-20 token on Secret Network. Wrapped versions of the SIENNA token exist on other blockchains. There is a BSC version of SIENNA, and an ETH version as wSIENNA. In order to move these tokens between the supported blockchains, the bridge will collect x amount on one chain, and release the same amount on the other side. The conversion is always 1:1, minus the bridge free.