Well, I ordered another brass signal and had it rejected because it appears that Shapeways doesn't allow sprues on their 'Precious Metals'. The sprues on my signals attach the various detail parts (signal arm, counterweight lever, lamp top, etc.) to the base of the signal the same as the Frosted Ultra Detail versions.
It appears that my first signal managed to slip past the person doing the design check.
I can only conclude that these metals are aimed at jewellry and they are limiting someone making jewellery to only one item, although they do allow a pair of ear rings and cuff links - go figure, it doesn't make any sense!
I have just withdrawn 12 brass signals from my Signals Branch shop.
The brass signals were expensive and I didn't think I would sell too many but it is still very disappointing particularly when you have a nice example of what could be made.
I am very sorry and apologise to anyone who was contemplating these brass signals.