Are these tradable FOR Seals? I know you can trade seals for them 250/1 is there someone who does this the other way around?

I know you can use them in 2/3s for sands/oil of time but I don't really see why you can't also trade them for allied seals to finish those GC sets faster.

I like how they are now but I'd also like to be able to "downgrade" them for when you get one off an elite mark and don't really want the Coil items. xD Thanks