Among the announcement from the latest Apple event is that the company is making the new Mac mini and MacBook Air from 100 percent recycled aluminum. The company says that its metallurgists have discovered a new method for using the excess aluminum from the production process to create the new alloy it is using to make its new Macs.
https://www.notebookcheck.net/Apple-now-using-100-percent-recycled-aluminum-in-new-Air-Mac-mini.354236.0.html