As you can hopefully see in the provided image, the belt filter is filtering out the exact shape that is being fed to it via the wire (the wire tool-tip is also shown).
The shape on the belt (that is getting filtered out - and trashed) is exactly the shape required and that shape is on the wire.
The shape is a single layer.
It's worth noting, however, that the pin quarter has been through a painter. Obviously, since the painter does not change the colour of the pin, this should not be considered different to an "uncoloured" pin, if this is the reason behind the issue. If the pin was to be considered "different" from an uncoloured pin, it should be visually apparent.