Actually, here is yet ANOTHER misattributed label I have in my collecton, and this one is from ANACS, who is supposed to be the expert in error and variety attributions. It says "Type 2 Blank" but it has a rim, so it should state "Type 2 Planchet." I guess these mislabeled errors happen more frequently than I thought!
Just pointing something out here. Do you know what burnished means ? It's just a fancy word for polished. Now those straight parallel lines that you see on the planchets labeled as "unburnished" - do you know how they got there ? It's because the planchets have been polished. It's just like it is with die polishing, polish, or repolish, a die, and don't do the final steps to remove the lines that you see - and you get straight, parallel lines on the die that are then transferred to the coins struck with those dies. Same exact thing happens with planchets. Polish, or burnish, a planchet and you get those straight parallel lines that you see on that one. The unburnished (unpolished) plachets are the ones with the irregular makes all over them. Somebody at the TPGs is either thinking backwards or is very confused !
So the raw metal 13 inch x 1,500 feet sheets of metal fed into the press don't bear those markings at all before this whole process even starts, and those lines are caused from one stage of polishing? Isn't some other layer of metal placed over that to make it more shiny and golden-looking, and then it is polished again?
The surface of raw coin strip, before the blanks are ever punched out, usually looks similar to these pics of yours - all rough and beat up looking. A lot of folks may not realize it but the polishing of dies is a multi-stage process. It starts out with a course diamond dust paste, and progresses in multiple steps with each successive step using a finer grit paste. Each of the early steps leaves the die polish lines on the die, with them becoming closer and closer together, and shallower and shallower with each step of the finer paste. Until finally all traces of the die polish lines are gone. It works the same way as it would for you if you were using different grits of sandpaper to sand something down. You start with course and finish up with very fine. With blanks, most are not polished at all. But when they are, whether for Proofs or the small dollar business strikes, the same kind of process occurs, but without the final polishing steps that dies receive. They don't care if the planchets have lines on them because most if not all of them will be obliterated when the coin is struck. That's why you can see the lines on the planchets. As I said above "burnished" is nothing more than a fancy word for polishing. If it were not for the polishing those lines you see would not even exist. The coin strip for silver, gold, and nickels is rolled out of an alloy, a complete alloy. No other layers of metal are added. The strip for clad coins, all kinds of clad coins, is layered. And that layer of metal you're referring to, that is done long before the blanks are punched out. And there is no polishing of the strip - none. The strip is produced and the blanks are punched out by the company who makes them. Then they are shipped to the mint. Again with no polishing having been done. As should be expected the surface of the strip, even in its final stage before the blanks are punched out, is rough when viewed under magnification. As the blanks are punched out they come off a roller belt. At various points along the way with washing and moving them from place to place all the blanks are all jumbled together, banging against each other and creating contact marks just like those that occur on coins after they are struck. That adds to the rough surface you see in those pics of yours. If there is any polishing done it is done by the mint, and it occurs to the blanks, before they go through the upset mill for that is the only way they can be polished. Once they are upset they can't be polished any more because of the raised edges - they have to be polished when they are flat. So before the planchets are ever annealed all of this is done and over with.
Polishing of planchets is done by tumbling in a chemical solution with steel shot. That's not going to give you straight parallel lines. The straight parallel lines are probably left over from the rolling mills.And there's not much reason for polishing blanks.