Healing! But particularily long-term healing. Rather than the knitting of open, gaping wounds the Tea & Tranquility Arcana can help patients regain their energy, fight insomnia and back-pain. Some of the more advanced spells are particularily apt at working against poisoning of any kind.
It has also been theorized that Tea-mages can help restore something so obscure such as mental suffering and mana-damage. Some mages that are terminally wounded by chaotic magic use, has seen significant improvement after a weekly session at a Tea-magus.
Tea has been used for medicinal purposes since the birth of the Citadel, ms. Pamparei of the Ivory always figured, so why wouldn't it be its own Arcana really? It's a fairly new Minor, barely ten years old, but some claim its practices have been used for centuries (although, to be honest, which new hip healing method doesn't claim just that?).
The Tea & Tranquility Arcana is closely associated with herbalists, therapists and alternative medicine. It's commonly an Arcana practiced outside of traditional healer institutations, and is most common in the Ivory and Azure Tower. Magi that master it work as personal guides, healers and conversation therapists.
HAVE FUN WITH IT. This is mostly meant to inspire conversational RP over a nice cup of tea - so go forth and conquer, get all the character backstory and such. Best suited for inquisitive characters, that ask a lot of questions while making a new pot of chamomille. Expect to act as ingame-counselor.