It's a color that pictures simply cannot capture - most pics just look black, or are so up close that it negates the impact. Best bet is to find one at a dealership - the effect is remarkable in the sunlight.
You really will have to see it in person, and you'll have to make sure you get to see it in the sunlight. I LOVE Sapphire Black. In all but direct sunlight (pretty much) you get a black car, and then in sunshine you get this gorgeous ultramarine blue metallic. It's subtle, but very cool. It might be my favorite color.
my car, sapphire black, pre and post-detailing. Sapphire is a lovely colour (but like many ark sades can suffer from swirl marks etc hence the detailing I had done) but it goes to a dep purple in lovely sunlight through a royal blue to a blackish hue.