I've recently started thinking that there might be a bug that prevents you from getting gemstones after receiving Hextech Annie. I've received my hextech prize pretty early, in May to be exact. Ever since, I haven't received any gemstones.
I've purchased boxes as well. I've opened more than 60 boxes since then and haven't received a single gemstone. The odds are very small that this happened on a pure chance. The usual count is 20 boxes for a gemstone. So I should have, by the odds received 3 by now. Receiving not a single one (when I did receive them normally beforehand) is highly suspicious. I'd be really thankful if Riot would check into this matter and tell me if there is a bug or I'm just unlucky.
If it is really a bug, I'd love to have it fixed, I'd also be kinda sad because who knows how many gemstones I'd have missed out. If not and I'm just unlucky, I'd love to continue trying XD