I recently acquired a beautiful example of a Drake Mercator Map medal (Photo attached) from the UK. The example I have is the type with the cartouche on the eastern hemisphere declaring that Mercator made the medal in 1589.

The medal weighs 584 grains, is 68.82mm diameter including the loop, and 67.61 mm at the widest point without the loop. The construction is two soldered plates, measuring 1.4 mm width at the edge. An image of the edge is seen between the two images of the medal. This seems to be one of the later electrotypes made perhaps by Ready at the British Museum (though missing any "R" on the edge as is seen), but at a mere .7mm for each of the two halves, meticulously made.

In researching this medal, I came across numerous references to the medal in the e-sylum, including Alan Weinberg questioning the common claim seen that here are nine examples. If in fact there are hand engraved examples, then there may well be less than nine authentic examples, but The Library of Congress has two examples from the Kraus Collection, one of each type, and on their site actually has a listing of the nine known examples here (see number 58 on this web page):www.loc.gov/rr/rarebook/catalog/drake/drake-catalogue.html#MEDALSANDPORTRAITS

To quote them:

I located the Sir John Evans example; now apparently down-under at the Library of New South Wales, with this provenance:

To read the complete article, see:acms.sl.nsw.gov.au/item/itemdetailpaged.aspx?itemid=825796

It is worth noting that the Library of Congress site includes a discuss the construction of the medal, with the earliest and most recent studies concluding that the medals are in fact die struck or cast and not hand engraved:

For me personally, having never seen any example of any of them other than the low-resolution images on the internet at the Library of Congress, National Maritime Museum, British Museum, and Library of New South Wales, I have no way to judge what is engraved or cast or struck.

As far as the example I have in hand, I know it has been said that that an electrotype can be precise down to a molecule - but it is impossible to make a matrix accurate to the original down to a molecule of tolerance, so electrotypes are always inferior to originals because of the matrix being only an impressed copy, usually created by hand. I have seen Ready electrotypes, and they are excellent in quality, but still notably inferior to the originals. This example at 584 grains is heavier than any of the nine examples listed above, so the weight certainly points to the possibility of an electrotype, but I have never seen any electrotype constructed out of two pieces that is this thin and detailed. From what I can tell even an electrotype is prohibitively rare, and other than electrotypes at the NMM and the ANS (and presumably the British Museum), I know of no other examples in private hands. The photo speaks for itself - this is a lovely piece - and a worthy addition to my collection!

From a cursory comparison of images I have located on the internet, I agree that they seem to be precise copies of each other, as the example I have matches all the others with a cartouche, including the electrotype at the NMM (though it is worth noting that the NMM electrotype has a smaller stated diameter of only 66mm).

Clearly more study needs to be done to see if there are in fact any engraved examples of these medals, and to sort out the method in which these were created. Without this detailed study, it is impossible to know what is authentic and what is not.

I thought this should also be added to the mix into the discussion regarding whether an engraved Drake Mercator Medal exists. On the British Museum website page showing the A.W. Franks example without the cartouche, they address this:www.britishmuseum.org/explore/highlights/highlight_objects
/cm/c/cast_silver_plaque_depicting_t.aspx

The medal(s) they have are not engraved, and this is their stated conclusion about the construction of these medals:

If in fact the Mercator medals in the incredible cabinet of the British Museum are not engraved, then I am leaning towards believing that none of the medals are hand engraved as stated by both the Library of Congress and the British Museum. websites. In addition to the Stuart medals mentioned, there was also a similar struck or cast medal made of Elizabeth I (by Crispin I van de Passe) emulating an engraved medal, but it is attributed to the early 17th century. In Medallic Illustrations, however, there are other struck or cast medals shown from the same 1580's period as the Drake Mercator medal which do emulate engraved medals, including a 1586 counter for James VI of Scotland (MI I 137/94) and a 1588 counter for Sir Thomas Heneage (MI I, 151/24); so the technology to strike or cast medals emulating engraved medals did exist at this same time.

To read an earlier E-Sylum article, see:DICK JOHNSON ON HOW THE MERCATOR MAP MEDAL COULD BE REPRODUCED(www.coinbooks.org/esylum_v13n25a23.html)