This NARS Duo came out for Holiday 2010, so I am a bit late to the party. Better late than never, right?
Melusine is a lavender-tinged silver shimmer and a warm purple matte. The silver has a pinkish flash which was nearly impossible to capture.
The silver is buttery smooth and highly pigmented. The purple is much sheerer and can be a pain to blend. It is workable though, and it looks gorgeous with the silver.
Here are some comparisons. I don't have anything quite like the silver, but you can see the slight warmth when it is swatched next to a true blue silver color.
The purple is nearly identical to MAC Fig. 1.
I definitely think the silver makes it worth owning this duo alone. NARS eyeshadows can be hit and miss, but this duo is a hit for me!