Not rare the ones on the left are normal and the other ones are just normal roll toining/color Change nothing special.
The ones imaged, No. when the plating solution is formulated it includes a small percentage of zinc, as the levels are topped up there becomes slightly above normal levels in the mix, this is what causes a quantity of coins in the production run to have a brass like look. when the zinc levels become to high a new batch of plating solution is produced and for a while the coins take on a more copper looking appearance. This is my understanding of the cause, and, as stated above, the others are just naturally toned
All cents start off as "Red" (actually a coppery color) and progress through Red-Brown to Brown, in the absence of factors other than atmospheric oxygen. Environmental factors can cause MANY color variations. Keep reading here in CT and you will find numerous instances of toned copper coins that people really treasure.
The grading companies rank them as RD, RB and B. For older coins, the RD carries quite a premium in most cases. I'll look for an example.
I'm just curious, what about these coins do you think might add a premium to them? They are Zincoln's and unless they have a mint error, they are worth 1¢.
They make Billions, yes with a B, of these every year. So no not worth more than 1 cent. I would not pay attention to those You Tube videos, they make their money off of clicks to their channels.
Copper tones in many pretty colors but it takes something special for it to add any value to the coin.
Once a coin is minted, it goes thru sweaty hands, dirty pockets, dashboards of cars.... Any of a billion situations. Each and every condition lends to the toning process. Quite simply, your cents are normally toned.