There are two most common types of copper pipe, #1 copper pipe and #2 copper pipe.
The difference between the two is pretty simple, #1 copper is clean copper pipe: no paint, no solder, no other metals or materials attached to it. #2 copper pipe can have paint solder dirt but no other metals or materials attached to it. There are few ways to go about recycling it, you can either sort your #1 and #2 or you could mix it together and most recycling yards will just go in the middle on the price.
The difference in price between the two is usually $00.10-$00.20 so if someone has quoted you $1.80 for #1 copper pipe and $1.60 for #2 copper pipe you can always mix them together and try to sell them for the average of $1.70 per lb. you always need to make sure that you don’t have any brass attached to it because that will bring your price down, most yards will have to buy it for copper brass mix in that case, it all depends on how much time you want to dedicate to this process, selling it for copper brass mix will save you a lot of time and in most cases will still bring you decent money, the price for copper brass mix is normally about $00.20-$00.40 less than #2 copper depending on the copper to brass ratio in your material.