What is the meaning of mantle?

I'm curious about a term I've come across recently, 'mantle'. Could you please enlighten me as to its meaning? I've seen it used in the context of cryptocurrency and finance, but I'm not quite sure how to interpret it. Is it related to a specific role or responsibility within these fields? Or does it refer to a particular aspect of the industry? I'm quite fascinated by the intricate terminology in this area, and your explanation would greatly assist me in understanding it further.