You are close!!!

The contents are close or may be it is an ingredient of Red Bull who knows. The "cup" or "Mate cup" is actually a small gord that is cut and then covered with leather. There is normally a rim that is put on it as well. Some have it some don't. I've seen just a plain gord. some even use a glass. The straw or "Bombilla" has an spoon at the end of it with a screen. I'll post some photos later to illustrate. Which gives me an idea. I will photo jurnal the whole process. The contents is a type of tea leaf. It is called "yerba". This tea comes in different brands and flavors. It has many medicinal purposes. But really the drinking of or the action of "Matando"(drinking ma-tea)is a very cultural thing here. I'll post some more later on how and why. Now some have said it favors a water bong. For those that won't admit it, yes it is similar as well. When I get my photos in line, I'll got through the whole process of preparing and drinking "Mate".