I just got a super haul of OPIs from Craigslist and have started the swatch madness. Meet OPI DS Mystery.
Here is a bottle pic.
This is after the first coat. It's not black, it's actually a super dark purple!!! It isn't really perfect at one coat though, so it might not be wearable like this. Maybe you could do it over a purple undercoat so it wouldn't matter as much.
And some swatches after 2 coats. See the gold/copper flakies?