Valve has announced the start date (and time) of the 2014 Steam Winter Sale, and come up with a way for people to recycle unwanted trading cards. The Steam Winter Sale date is confirmed as 18 December (at 10am Pacific) in the “How it works” section of this page about said system.
But why would you want to recycle trading cards, crafted emotes or backgrounds? Well, because until 18 December (prior to the Steam Winter Sale,) there’ll be some ongoing game auctions.
To bid in the game auctions, you’ll need gems. And the way to get gems is to recycle your unwanted Steam community items.
The first round of auctions is already up (on the page linked above,) and will end on 15 December at 7.00am (Pacific.) From that point onwards, it sounds like there’ll be “a new round ending every 45 minutes until the last auction round ends on Dec 18 at 10:00am.” The top gem bidder at the end of each round will win the game.
As you’d imagine, badges, backgrounds and emotes have a higher gem value than regular trading cards. It also looks like you’ll be able to use spare gems to create trading card booster packs. Unfortunately the link pointing at that particular page isn’t working at the time of writing. It may be by the time you’re reading this, so give it a go.
For more details about Valve’s latest bizarre economic experiment with virtual goods, read the FAQ on the auction page.