Confinement - S2-E5
Continuity mistake: Ruby asks Ash where the the Kandarian Dagger is. He says that it was confiscated by the police. In the previous episode, she had and used it, and they have not interacted in the intervening time period.
Continuity mistake: When Alicia is cleaning up Nick's vomit, she removes her gloves. When the angle changes, she starts removing them again. (00:24:45)
Revelations - S1-E10
Continuity mistake: When Piper reveals herself as the killer in the dock, you can see her dropping the mask and shortly after, removing her poncho and drop it on the floor as well. In the next shot from the side of the dock where you can see Piper and Emma face to face, the mask and the poncho are no longer on the floor. (00:32:20 - 00:33:10)