https://wccftech.com/apple-mass-2022-iphone-se-using-carbon-free-aluminum/

As part of its efforts to conserve the environment, Apple has stated that it will start using carbon-free aluminum to mass produce various products. For the time being, it will produce the 2022 iPhone SE utilizing this material.

Apple has started purchasing carbon-free aluminum to reduce emissions. Thanks to advancement in smelting technology, this aluminum is the first to be manufactured at an industrial scale outside of a laboratory, with the intent to manufacture the chassis of the 2022 iPhone SE.