u/Im_S0_Confused

About two years ago, I was sitting next to a small stream in Munich, killing time before my flight home. I saw something shiny in the dirt, and started poking around it with a stick. I ended up digging this thing out. Two years later and I still have no clue what it is. It's quite hefty, and some parts are transparent, making me think it's either glass of crystal. I'm dying to know what it is.