Below you can see a photo of rolled blue steel (left) and pickled steel (right). With pickled steel, the mill scale has been removed.
Visual characteristics of mill blue steel are:
- Color: blue-gray to dark blue or even black.
- Texture: Hard, brittle, and slightly flaky.
- Finish: Often matte and occasionally slightly shiny.
Please note that rolled blue never looks the same. Sometimes there is more black visible than other times. Sometimes there are no black spots at all and the blue color may be less intense. The surface is designed for functionality.
How to recognize rolled blue steel :
- The surface appears bluish, dark, and mottled.
- The surface feels rougher than blasted, ground, or cold-rolled steel.
- The surface may flake off if damaged, revealing the lighter steel underneath.