Why does aluminium foil have a shiny and a dull side?

Is There A Right And Wrong Side Of Aluminum Foil?

Aluminium Foil, which side up? Shiny IN or OUT? - Warren Nash

Why does aluminum foil for food have a shiny and a dull side? - Quora

Easy Baked Salmon Recipe

Shiny vs. Dull Foil

The difference between the shiny and the dull side of aluminium foil

You're using aluminum foil wrong: Here's how to use it right - The Jerusalem Post

Tin foil – shiny side up or down? - Blue Sky Questions

Should You Use Aluminum Foil With The Shiny Side Up Or Down?

What's wrong with the aluminum foil in Vietnam? I have lived here 12 years and always wondered why some brands of foil always come out like this And if it's safe to

When using aluminum foil, does the orientation of the shiny side vs. the dull side matter? - Quora