This shelf is made of a U-shaped aluminum plate with a t = 3 mm.
It feels like I picked it up in a factory or found it in an antique market.
I had an image of using a strange material as a shelf. I heard that stainless steel hairline is good to be calm. Is it true? Actually, it's not enough recently. The luster of the aluminum is a very good accent in a space that is too calm. Not only can it be fixed to the wall, but it can also be placed on a large table and used as a display stand in shops.