Necromantic Aegis
The Necromantic Aegis keystone passive skill gives the following effects:
This includes any implicit or extra mods to your shields, so spiky shields will provide damage reflection to your minions and added fire damage will add fire damage to their attacks.
Tempest Shield will NOT be transferred to minions. Passives Skills that increase Shield stats will also have no affect (i.e. Energy Shield on Shield, Bulwark and Shield Block.)