In addition to the items previously mentioned (Music Box, Nail Case, Lion's Heart and possibly Tin Key), the Golem Wrench, Percht Skull (which you turn in), the two Tendril Lanterns can't break. I also believe Library ticket and Regalia of Suon falls into this category, but I need someone to confirm.
I only know that the Lion's Heart (noble lion taming item) and the Nail Case(Gravedigger taming item) cannot break.
The itens that are no breakable are the itens from quests:
Other items that do no break are the eggs: Menacing egg, Crackling egg and Vibrant Egg. Same for Astral Shaper rune and the glooth glider rider.
All the others has a chance to break, even some of them it's minimum.
TibiaQA Quick Tour design contestJanuary 06, 2020
Can I post my entry as an external link?January 24, 2020
Idea for new section: Owners of Omniscient OwlJanuary 21, 2020
Can we get notified by email or on our profile if someone edits our post?January 15, 2020