Hi, I listed what I thought was a fairly low value 1969 Hong Kong University First Day Cover on Hong Kong and I've had several people offer me silly amounts for it and I have no idea why it seems to be attracting so much interest.
I can only assume it must be the cover itself rather than the stamp/postmark, but would really like to find out more about it and was hoping somebody could point me at some information about it.
Many thanks in advance.
.