2 coats, no top coat
I really do love this. I've found the quality of MAC polish has changed in the past year or two... I had it on for 4 days before I ended up having to take it off because I ripped my nail really low and had to patch it. I then trimmed them all down because I can't function at work with really long nails (that's how I ripped it in the first place).
Here's my comparison of it with Peridot.
|Left to right - Immortal Gold, Peridot, Immortal Gold, Peridot|
As you can see, they're similar but not identical. Immortal Gold is just more of a very green gold without the duochrome flash that Peridot has. Peridot has also more of a foil-y finish than Immortal Gold does.