In the Comex there is virtually no physical change of ownership, its all paper trading with only a very small percentage of physical in the warehouses behind it to give an aura of legitimacy and credibility to the Comex.

Most of the physical deliveries are via the http://www.lbma.org.uk/ otherwise via Switzerland, etc.

To use a favorite of Benny B it's all about managing "perceptions" considered more important than realities, BB's words : Fed has "Gold Plated" security (interpretation no longer backed by "Solid Gold"), the same shine, counterfeiting its own currency has now been legalized as time and again in the past.