I was going through my Canadian large cents to put some on ebay when I came across this one. It was with my duplicate stash of large cents. I don't remember any looking like this when I first got them. What would you grade it? Check out this major grease filled die(I'm assuming)
I would grade your 1920 Large Cent at AU or perhaps even UNC. Worth perhaps $6-$10 in AU and $20 in UNC (MS60). Your 1900 has a very badly worn reverse and overall I would grade it borderline GOOD. I don't have a reference that lists a value for that grade but would guess it's worth $2
I'm pretty sure the 20 is in Ms+ condition and this dramatic toning should get a higher premium. The 1900 reverse is a grease filled die strike. I was just showing it off because its a large one.
I think I agree with freezer burn on the AU. It would be MS but it looks like the leaves have wear on the tips, could just be the photographs though. I love the colors though, great job getting the colors to pop.