I just had a couple of questions on maybe about 10 to 12 coins so I posted them separately besides these two cause they weigh the same and both of them which looks like numbers of 77
They are zinc, they are supposed to be around 2.5 grams. 2.45 is fine for a zinc planchet. Both have no errors. The colors on the 1999 is colored because of contact with some kind of substance/acid.