Clear Object Drawing

​In this drawing, I really wanted to show the lines that actually formed the cup. I noticed how when you see something clear, it basically shows you the edges and everything (including the edges on the inside). That is what I tried to accomplished.

Materials I used for this were just a plain old pencil, paper, and charcoal. I tried to do some shading, but was confused on where to actually shade, since I didn't really see shadows. At least, I didn't think they were shadows, they were more link glossy areas after the edges.