*CTV was introduced in February 2015*
Gold bordered cards in PackRat are any cards that have a Card Ticket Value (CTV) associated with it. A given card's CTV can be based on how many tickets it cost to buy, how many tickets it cost to make (if a recipe card), or a random assignment of CTV by the Rats, in FlipRat, for example.
If you purchase a card with tickets from any non-auction market (including bling and lock cards), it will automatically have a gold border added to it, along with a leaf in the top left corner, signifying that it is permanently safe from being stolen.
The one exception is if the card is purchased with tickets from the Moscow Auction house: if the card originally didn't have a gold border, it won't have one after buying it with tickets from the auction house. If the card originally had a gold border, it will retain this gold border (but NOT the leaf, if originally purchased with tickets) after buying it with tickets.
So while cards purchased from any other ticket market always have the leaf icon and are therefore permanently safe, cards purchased with tickets from the auction house, even if the card originally had a leaf, are only temporarily safe!
Some players really love the gold borders, while some really dislike them, so PackRat has a setting built in to the game that allows you to turn off premium borders, which will remove the gold border from cards (but not the leaf, nor the CTV). If you click on the gear icon from the top right of your PackRat screen, and then click settings, unchecking the "premium borders" field will remove these borders.
A couple of things to remember with gold bordered cards:
-If you purchase a lock card with tickets (including the Pack Pet lock), the lock will have a gold border when you see it unused in your Pack; once this lock is applied to a card, it will lose that gold border, unless the card to which it's applied originally had a gold border.
-If you purchase a bling card with tickets, the bling card will have a gold border around it, and adding it to any card (with or without a gold border) will add both the bling and the gold border. If you buy the same bling with credits and add it to a card without a gold border, no gold border will be added.
-If you purchase a bling card with tickets, apply it to a card, and then later remove the bling by using the scrubber (eraser) gadget, the card will still have the gold border AND the CTV of the bling originally on the card, even though the bling itself will no longer be there.