Hi Julian,
The Gaunt Birmingham mark is noted on the Forum by several posts by Martin. He notes the one from the Walter Lambert Collection sold by Wallace & Wallace with this mark.
http://www.britishbadgeforum.com/for...unt+birmingham
There are several other articles by Martin on the Gaunt history and they all note the existence of the Gaunt button business with London and Birmingham addresses pre-1900.
It would appear that 1st VB Leicesters badges bear the Gaunt B'Ham mark as a genuine mark and it poses much research potential as to what other VB badges they made and marked. Then there is the issue of blades versus lugs on such marked badges.
John M. posted a pic and reference which I will locate in the WO records of VB badges and it would be good if these could be consulted for clues. The Leicesters page which he photographed did not show a standard tiger cap badge but eth three lions pre 1905 version and that helps with the dating which I tripped on.
Assistance appreciated as the VB badges deserve more research and I think more information is out there than we generally acknowledge.
Regards Dean