I bought this eye liner a year or so ago, and it is a very beautiful and pigmented eye liner. It is black with an olive green tint to it, and that's what makes it unique. Black Line also has nice glitter/shimmer, but the texture of it is not gritty. I would not use it on my waterline, however, because the glitter is probably not safe for eyes.
You can see from the photo above that I had a little battle with the eyeliner sharpener. lol
What do you think about Black Line? Do you like MAC Cosmetics? You can still purchase Black Line on the MAC website.