Well done Bryn!
Any chance of a picture of the underside + pontil mark on the psychadelic pink one?
The mark impressed in the IOWSG pontil blob represents a gather of glass in a flame, the IOWSG logo. Is this what you mean by the bullet?
There are other marks other studios impress in their bits, sometimes these marks can be a bit squidged and difficult to make out, unless you know what you're looking at!