That's a glass cut. The orange you see is the rubber layer Conti uses as puncture protection. Depending on the size and location of the cut, you might still be able to get more miles out of it. If you decide you wanna try to get more miles out of it, I'd recommend you put it back on the rear.

These days, I buy my tires in groups of three. I mount two and have a spare for such damage. If I don't have any damage and simply wear out the tire (it's always the rear that wears out first) I move the worn front tire to the back and install the spare on the front and buy a new spare to put on the shelf.

-Kedosto