In my language (German) this type of cabbage, hast depending on region different names. Some call it blue, some red cabbage.
The red cabbage has a color that is exactly between red and blue. In the Middle Ages there was no word for this hue. "Lilac" - a word of Arabic origin - has only been familiar with the German language since the 18th century, Before only the full-tone adjectives "blue" and "red" existed.
I say sometimes blue, sometimes red cabbage. Depending on the dish I make. Adding vinegar or lemon juice (acid) it becomes redder, adding an alkaline like baking soda, it ends up more blue. Today it was more red than blue.
There is not only physics in cooking, but also a lot of interesting chemistry. Not to forget about the beauty of this vegetable, when slicing.
I'm fascinated with the colors and pattern. This image keeps my eyes moving through it. I'm trying to figure out what is on the left. My husband is a knifemaker/blacksmith so I'm familiar with the type of pattern on the knife blade too. Beautiful!
(we call it red here in Nova Scotia)