Every flavor will feature a little drop of chocolate garnished with a little edible gemstone.
You've already picked cooked meals based on your astrological sign—now it's time to eat Kit Kats based on your birthstone. Kit Kat is going to be rolling out its line of "edible birthstones" in Japan this year, releasing one every month. This month, they released the first, inspired by topaz for November: a chestnut flavor with a bit of amber-colored decoration.
Of course, you can't actually flavor a Kit Kat like a stone (because that would be terrible) so all the flavors are inspired by their namesake birthstones in color and decoration, but not in flavoring. Some months are more contested in their birthstone than others—January birthdays won't have much to complain about with their raspberry-flavored garnet Kit Kats, but October babies may be disappointed to find a tourmaline-inspired peach Kit Kat, rather than an opal Kit Kat, and some June birthdays may have been hoping for a pearl Kit Kat, even though the blue moonstone-inspired coconut Kit Kat is probably one of the better ones. (July is stuck with a ruby-inspired tomato Kit Kat.)
Each limited-time Kit Kat flavor will be released at the start of its corresponding month. Every flavor will feature a little drop of chocolate garnished with a little edible gemstone. A pack of three sticks will cost 1,485 Yen (about $13 at current exchange rates), which is a little pricey, but maybe worth it for the novelty of trying flavors like February's amethyst-inspired haskap berry flavor or March's aquamarine grapefruit mint.
Japanese Kit Kats are famous for their wide range unexpected flavors, although announcing twelve at once is a lot even by Japanese Kit Kat standards. You might remember the super bizarre cough drop-flavored Kit Kats, the gorgeous cherry blossom-flavored Kit Kats, or the actually alcoholic sake Kit Kats. Next month, for December's tanzanite, look out for the purple yam flavor.