Jasmine,as a life wizard i received these shields at the Arcanum,one is named Indemity the other aegus.Both are to protect but I have no idea how they are used or to protect me from what.
These are Sun School spells and behave similarly to Potent Trap or Sharpened Blade. The either prevent your Shield/Blade from being removed (Aegis) or they make it so the enemy can't remove their "Trap/Weakness" so ie. Steal Ward doesn't work and it needs to be cast 2X in order for it to work.
Aegis is for positive stuff like your blades and shields if you think your enemy will earthquake or something Indemnity is for negative stuff like traps (feint) and weaknesses (prevents enemies from switching traps with you etc.)