The mirror that I'm talking of, is situated in Hazarduari Palace in Murshidabad, West Bengal, India. This place was once the capital of Bengal under the Nawab before the British defeated the Nawab in the historic battle of Plassey, 1757.
The history is not that important here, but the mirror is. In fact, this is not a single mirror, but a set of mirrors that adorn the so-called "dressing table" of the Nawab. The importance of this set of mirrors is that, when you look at it, you can see everyone around yourself, but not yourself.
When we had visited this historic place, we also got a chance to see this famous mirror set. Whether you look at it from a distance or very close, you'll never be able to see yourself, but you will clearly be able to see everyone standing next to you.
As it was a museum, photography was prohibited there, due to which I cannot show a photo of the mirror. I searched on Google but couldn't find a photo, perhaps due to the same reasons. So you've to believe my words that something like that really exists.
Now, my question is, can anyone show or explain how such a wonder can be created with plane mirrors? I've never seen it elsewhere. How can you not see yourself but everyone around you?