The Mac Observer has discovered that you can recycle your physical Apple Card using the Apple Trade In program.
Recycle an Apple Card
When you want to close a credit card, you usually cut it up and throw it away because it’s plastic. But what do you do with a metal card? If it’s an Apple Card, you can use Apple’s Trade In program.
This program is for recycling all kinds of eligible Apple devices and you’ll receive credit towards your next Apple purchase, or an Apple Store Gift Card. If it’s not eligible for credit, Apple will recycle it for free no matter the condition.
To recycle an Apple Card, visit the Trade In page, click on “Other Devices” and find Apple Card near the top of the dropdown menu. When I clicked through it didn’t give me a price estimate, instead it asked for my shipping information. So it sounds like you might not get credit for a credit card. But it’s still good for the planet.