I had to look up Qalo rings, new to me. I think I see what you're getting at.
Besides Qalo, there are ceramic rings.
There are semi-precious stone rings (this one is jade).
There are amber rings.
I could go on. They all have one thing in common: they are bulkier than metal rings. If you want something you won't notice on your finger, get metal. That's why people began wearing metal five thousand years ago.
This is one I picked for myself.
The inscription "Vous et nul autre" is 15th century French for "You and no other." Original, no? It is a copy of a 15th century poesy ring in the Victoria and Albert Museum, London. V&A is the greatest knickknack museum known to me. During the European Renaissance, a poesy ring was a popular cheap gift to someone of romantic interest. Shakespeare thought it was cheap romantic kitsch.
This one made my wife happy, which was its intended purpose. It is sterling silver. If you choose gold, I recommend 14k. 18k is too soft for a ring.