I picked up a Canadian quarter at the TNA last weekend. The grade from PCGS seemed a bit off - it looks proof-like to me, but has an AU-55 label. There weren't proofs made in Canada in 1948, but there were presentation pieces. Are there any telltale markers for the presentation strikes?
Canada made BS coins for normal circulation, and they also made proof like coins and sets intended for collectors. I am not sure how far back that goes. I know at least the 1950's.
I couldn't quickly find an authoritative reference for when the "proof-like" era began for Canadian coins, but https://www.coinsandcanada.com/coins-prices.php shows when the designation started for various denominations according to them. For the quarters and half dollars, 1951; for the dollars, 1949; cents nickels and dime, 1953 with the QEII coins. Specimen coins go back to the Victorian era. By "presentation strikes" I assume you mean the specimen coins. This is an interesting topic, because years ago I proved that specimen dies were reused for circulation strikes. There had been speculation about it before. I demonstrated that specific die markers were found on both SP and MS coins for the 1947 Maple Leaf dollars (struck in 1948), the 1948 50c, and the 1949 50c. I don't recall investigating the 1948 25c, but you'd have to find identical die marks to search for. Because specimen dies for dollars and half dollars struck in 1948 also struck MS coins, you could speculate that the same occurred with the quarters. I could argue that there should be a "specimen-like" designation for these MS coins. My 1947ML dollar, where I first noted the SP die marks on the reverse, is distinctly more reflective than my 1948 dollar, both in MS62. It's like a mirror. The bottom line for your coin is that it could have been struck for circulation from specimen dies, but you're not going to get it designated as such. As an example, here are the die marks on the 1947ML $1, MS and SP.
