Transmuting arcanite has a 48h cooldown, transmuting essences has a 24h cooldown, transmuting 1x heart of fire into 3x elemental fire has a 10m cooldown. I think mithril->truesilver is also 24h, but I'm not sure. It's a waste of a CD any way.
Mithril to Truesilver used to be 48 hours in retail vanilla, that i know for sure.