Spell Crit should work on anything that uses Magicka since the patch where they aligned weapon damage and crit to stamina abilities and spell crit/damage to Magicka.
...OverTwerked & Underpaid. Rajaat04 in game @Athas24 on forums
Even a WARD? Everything I've seen -literature wise- says "damage/healing"... a ward is neither...
Can you crit on a ward to double it's soak amount? Anybody know?
If you are talking about a shield then I don't believe crit has anything to do with it. Heals that are DOTS don't use crit either so I'd say its safe to say a ward doesn't if it's a damage or spell shield.
...OverTwerked & Underpaid. Rajaat04 in game @Athas24 on forums