Not in the best condition, but would the crown be considered small or large?

My dad recently gave me a bunch of old coins, this one most detail is gone but has the queen on rear, anybody know what it is?

Noticed on the rear of my uncut sheet that the serial number, word "Canada", and "One" seem to be engraved onto the back of the bill. Is this something I should bother getting appraised?

Thanks that would explain the diameter increase, what about the thickness increase?

I have recently found this 2000 penny. It appears to be a full zinc core without any copper. Knowing that someone can chemically remove the copper, I took some measurements of the coin. Normal zinc core 2000 penny per Royal Mint: Diameter: 19.05mm Thickness: 1.45mm Weight: 2.25g Copperless coin Diam...