I found Pink Pearl by W7 for £1.99 on my local cosmetics stall. I had a sneaking suspicion that it would be sheerer than sheer, but it had such ethereal pink flecks in it that I couldn't resist anyway!
The pics below show 3 coats of Pink Pearl on its own on my index and middle fingers, then 1 coat over a baby pink on the ring and pinky fingers. Photo 1 is in natural light, Photo 2 with flash.
I wish I could have photographed the shimmery flecked pink better, but it is really lovely over the base colour. Definitely a layering polish though! Normally I would avoid such a polish but the finish of this is so nice that I would go for it. Not a boring pearl!