I just purchased and received this lot of chips from an Ebay auction. Trying to determine chiprack numbers for most of these chips. As you can see, most of these chips are older chips and the seller said this in her auction:

My husband's parents brought these home to him from there trips to vegas in the 70's some might even be from the late 60's.

Question #1: On page 275 of TheChipRack (ninth edition) I was locating the Silver Slipper 50¢ chip. Appears to be "N2180" but description indicates that maybe these are not valid chips. Since this chip appears to be from an older collection/lot, maybe this is a little information that indicates that these were actually used and not imitation chips???

Question #2: The $1 Sahara chip in row #5 has scotch tape over it. Really dried up stuff. Do I dare try to clean this chip and what should I use to remove that tape?

Question #3: I know nothing about the Colorado chips in the last row. Can anyone help me with the value/age of these chips?

Thanks,

Brian