I am in question on how people collect/catalog Harrah's slot cards. It seems that they are collected by the beginning 3 digit number where the account originated. Or is there another way to collect?

Top card in my image is a slot card from where the account originated Harrah's Council Bluffs.

The middle card is the back design used at the Iowa properties. Notice the Bluffs Run logo on the left side.

The bottom card is a card I picked up from Bluffs Run Casino - However my account originated 12 years ago at Harrah's Laughlin, hence the Harrah's Laughlin number. So is this a Luaghlin or Bluffs Run card?

So my question is do you collect by the card design and where the card was actually picked up or do you collect Harrah's cards by the account number?