Below: Drama In The Dark, also off-black based, is a deep charcoal blue shade with silvery blue glitter.
Below: Black To The Future is, you guessed it, another off-black based shade, this time in purple. The glitter is almost a violet shade, making it light enough to have a bit more impact against the background than the other two shades shown.
Today I have a couple of my untried's from the Nicole by OPI line, which I purchased at TJ Maxx several months ago for $3.99 each. All of these are either black or off-black based glitters, and although they're rather dark, the glitter still sparkles through the background quite nicely. I used 2 coats on all of these and had no problem with the formula. All in all, I like Nicole's polishes but I don't like the bottle shape at all. It's a non-conformist and is difficult to hold for photographing. It takes up more space than it should on my shelf due to the shape, but most of the shades are nice enough to overlook that issue. I've always been drawn to black-based shades with tiny glitter, so I was happy to pick these up at a great price.