Couple of questions about Raven-Touched Shard

1. I presume you cant anoint Zarokhs Gift on Amulet and Helmet and have 2 sinister jewel slots?

2. When anointed via Raven-Touched Shard, is it permanent or can you change anoints like on amulet (if not corrupted)

3. If i have 2 or 3 sockets on helmet, will the shard destroy the other sockets making them unusable?

Thanks!