This is the Mercator model which came out in honour of Gerard Mercator, the cartographer's 500 anniversary.
Limited quantities were made. they all featured reproductions of Mercator's maps.
The one pictured is of North and South America although there are others with different parts of the world pictured, some with only local maps (ie Portugal, Germany) and others with continents like the one pictured.
I believe the one in your photo is platinum with the etched face. They were originally done in a cloissonee fashion.
There are still a few floating around for sale but are very hard to find, especially the cloissonee ones.
They haven't been made for about 10 years. That's why they're not on VC's website.
If you send me a private message I can send you a link to a site where there may be one still available, but in yellow gold, not platinum.
They also appear on the auction sites periodically (Antiquorum, Sotheby's and Christies.)