The colourful pearls are in a colourless liquid and once you pump the primer out, the pearls get crushed by the pump, so you get a smooth, cloudy runny gel as a result. I can't say how mattifying exactly it is, or how long it makes your make up last because I haven't tested it long enough, but it certainly has some effect and I do love how smooth it makes my skin once it's applied.
At £23 per 30 ml it is a much cheaper alternative to the Guerlain Meteorites Pearls primer, so if you always wanted to try that one out, but didn't want to pay the high price tag (I think the Guerlain one is now £42!), then give this one a go. I bought mine from BeautyBay, I don't know if it's limited edition or not, but at the moment it's not available on the site. Hope it's not limited edition, because I would definitely repurchase this when I run out.
See more pictures after the jump!