Y Z?

Why does Goldfinger choose a "Z" for his gold bars' vanity mark? I've searched again today and found . . . Zip. Zilch.
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Why does Goldfinger choose a "Z" for his gold bars' vanity mark? I've searched again today and found . . . Zip. Zilch.
Comments
in Rush's case thats YYZ, the three letter code for Toronto's Pearson Airport
doesnt really help Goldfinger though, its nowhere near Fort Knox
Z for Zurich I presume?
I like the way you think very much, but Auric Enterprises was located outside Geneva. Goldfinger did Keep gold in Zurich but also in other cities around the world. Any other concepts?