100% copper-plated zinc vs. 94% steel/4.5% copper/1.5% nickel
2.25gr. vs. 2.35gr.
mintage was 759,658,000 vs. 30,525,000
"P" means coins were made with planchets from Canada (with steel, then magnetic). Coins without mark were made with imported planchets with zinc (non-ferrous, not magnetic). Few "2005P" non-magnetic exist due to the RCM using dies made for steel-cored blanks on zinc-cored blanks.
Sapientiae plerumque stultitia est comes.
Si c'est un grand plaisir d'être reconnu par ses amis, c'est peut-être encore plus flatteur d'être reconnu par ses adversaires.
Be yourself; everyone else is already taken.