Fruity mate
In countries like Argentina and Uruguay, mate is a traditional infused drink. What one actually drinks is yerba, a dry leaf served with hot water in a container, the mate. Most people have it neat, but some tend to put all sorts of things inside the mate.
The most common thing to add to mate is sugar or sweetener. Some people like their mate with coffee, and some adventurous people will sprinkle orange or lemon zest for a fruity flavor. This photo looks like a mate with blueberry circumferences on top.