Oh, Sorry! Language-slip! ( I guess my english is getting a bit rusty ) An aquarel is a watercolorpainting made on wet paper, I dont know what the english word for it is). The term is also used to describe the special paint and paper, I guess its slang. What I do know is that the word originates from french.
I once painted a series of aquarels with coffee. One can regulate the color with water like with regular aquarel-paint or one can regulate the coffee it self; make it more concentrated for darker brown. It makes sort of a sephia-effect, and you get a feeling of painting old pictures somehow These paintings will not last for ever, they will bleach faster in the sun etc, but I painted mine back in 2001 and they are still holding up.