I believed all 25 mm medals were made with Thomas Shingles obverse.
(first picture of your last post) I haven't seen a PM on any of
those 25 mm bronze sized medals. Your medals show little wear
with some original luster. Nice.
BUT - my assumptions were wrong, I am looking at your
medal and it is a Metcalfe - the 25 mm one. The bust
portrait does not go all the way to the bottom rim of the medal
which is a big feature of the Shingles 1 inch or 25 mm medal. I
have looked at quite a few medals and none had the PM but all I
have seen up to this point were Thomas Shingles medals with
portraits touching the bottom rim. Obviously some were struck with
the obverse dies of Metcalfe when they arrived later, but
with no engravers initials, a key difference in the
larger sized medals designed by Metcalfe.
The Mint had to improvise a bit with a deadline looming to press
enough medals for Canadian school children, the obverse dies being engraved by
Metcalfe were delayed and the Mint employed Thomas Shingles to
engrave an alternate obverse so that medals could be distributed
on time for the arrival of the King and Queen in May of 1939.
2,533,943 - 1 inch medals were struck in bronze for all school children of Canada.
(This info from the Annual Report of the Mint Master 1939-1940.)
"Given the need for over 2.5 milion pieces, the school children's
medal had to enter production first. It did not have to meet the
rigid standards of the other medals so production of the dies was
contracted out to a Winnepeg firm. The task of engraving the
master tools was entrusted to the firms finest engraver, Thomas
Shingles... ... Production began with the dies engraved by
Shingles. When the Metcalfe obverse arrived from England,
however, it was employed for all subsequent strikings."
Dr. James A. Haxby - Striking Impressions - The
Royal Canadian Mint and Canadian Coinage, page 162
Thanks PennyBox and welcome to the exciting world of medals and coins.