As always I keep researching
and have in some degree answered my own question on these VOC balemarks and associated dates and chamber marks.
In my notes I discovered a Javanese badhik with cut down blade that has the R (=Rotterdam) mark (the date obscured 1746?). Also a Scottish baskethilt with a blade that has the VOC and stylized A in an opposed configuration that has the two incorporated into a diamond effect. The date '1787'....another blade of flattened hexagonal form similar to 'dragoon' blades made in Solingen for Spain in the 18th century, has the same logo in diamond shape, the date 1787.
Other unusual blades of straight form I have found seem to have carried the 1775 date, while another is on an English hanger dated 1794.
It would seem that 1787 was some kind of a banner year for blade production!
yet these variations in the Amsterdam motif suggest different place or maker.
Again, most of these blades I have seen date 1767 + to 1794. Why these selective dates, and why on blades while weapons other than cannon, as far as I know were unmarked.?
Anybody out there with VOC bladed weapons or knowledge on the VOC that might be able to offer some examples or ideas?
All the best,
Jim