Non Bank Safety Deposit Box in Zurich/Zug

I'd like to store a smaller amount of gold and documents in a safety deposit box in Zurich or Zug. Can anyone recommend a really good company? I'm very cautious and aware of risks so I'd prefer a very stable and reputable company. I don't trust banks not to collapse so I need a non bank solution.

I already found Degussa and Philoro online but wondering if there's more?