Commems Collection Questions: Answer #24 - Silver Norse Medal Thicknesses

Spence asked about the Silver Norse-American Centennial medals:



I wish I had access to raw examples of each variety, but I only have encapsulated examples in my collection at this time. So, I have no way to accurately measure the thickness of either. So, I have to go into "report what others say" mode...(Maybe another CCFer with an example of each variety and a caliper can make some accurate measurements for us?)

Noted US commemorative coin expert, Anthony Swiatek, in his book - Encyclopedia of the Commemorative Coins of the United States - states
the following:

- "Thick" variety: 2.0 cm (20 mm) - Other sources suggest values in a range of 2.1 to 2.4 cm
- "Thin" variety: 1.6 cm (16 mm) - Other sources suggest 1.3 cm

My experience suggests that Swiatek's measurements should be considered good approximations vs. definitive results - I have encountered pieces that were slightly "thicker" or "thinner" and thus believe the thicknesses of the medals to vary slightly.

I struggle a bit with the "Thin" thickness specification of 1.6 cm when relative thickness between the two versions is derived based on the size and weight of the medals. Each of the varieties has the same width x length dimensions: 30 mm x 29 mm and are of the same fineness - 0.900 fine silver. Per Numismatic Guaranty Corporation (NGC) the weight of a "Thick" medal is 19.57 grams, and the weight of a "Thin" medal is 12.4 grams. These weights produce a Thin-to-Thick ratio value of 0.633586. Multiply this ratio by 2.0 cm (reported thickness of "Thick" medal), and you get 1.2672 cm for the thickness of a "Thin" medal - this argues for the reported 1.3 cm thickness for the "Thin" medal rather than 1.6 cm. Conversely, if you divide 1.6 cm by 0.633586, you derive a "Thick" measure of 2.52 cm. This is beyond the consensus measure of a "Thick" medal, so it appears that the 1.3 cm measure is more likely accurate vs. the 1.6 cm measure.

As far as tolerances, I have not seen specific tolerances for the thickness of the medals. My experience, again, suggests that the medals did not have the same strict tolerances as US legal tender coins as variations are out there.

I've read that the planchets for the "Thick" variety were punched from the metal used for US Silver Dollar planchets and that the "Thin" variety planchets were punched from US Half Dollar stock. Peace dollars are 2.4mm thick and Walking Liberty half dollars are 2.15mm thick. ICYWW, the standard thickness of a Standing Liberty quarter is 1.75mm.

As the Dollar/Half Dollar thicknesses don't correspond well to those of the "Thick" or "Thin" varieties of the Norse-American Centennial medals, I'm not convinced of the proposed Silver Dollar/Half Dollar links. I'll be more on board with the hypothesis when/if I encounter a Mint statement about the source planchet material.

This is a bit of a long-winded response, I know, but I hope it sheds some light on the answer to your query. My thoughts? In short, thicknesses of ~2.0 cm for the "Thick" variety and ~1.3 cm for the "Thin". (Subject to accurate measurements!)

1925 Norse-American Centennial Medal - Thick Variety