This OPI Alcatraz... Rocks, a Liquid Sand (aka texture) polish, which was in my favorite OPIs list:
other people's pictures that it looks darker than my swatch here.) It looks more navy with two coats but you can see here it has some violet tones to it - besides the violet glitter that's popping up very obviously in this picture. The glitter is actually very multicolored. This was in the San Francisco collection originally, but I believe this is still a current color.
And like many glittery textured polishes, it also looks awesome top-coated. (Basically, you're trading texture for extra sparkle when you do this.)