"Fredxx" wrote in message
...
The mirror is approx 400 x 700mm and is 6mm thick with edge bevels that
reduced this to 3mm.

It has no mounting holes and I don't want to drill any.

I can get mirror corner mounts but these are designed for 6+mm glass, and
conscious the mirror will rattle around in them.

Is there a better way?

You can use double sided tape but you need to be careful
using it because it can be tricky moving the mirror later,