It's a Rombus

On Saturday morning, Clara formed her fingers into the shape of a diamond.  I said to her, "What shape is that?"  She said, "A diamond!"  I was about to say, "Very good!", when Hailey said, "No, that's a rhombus.  I learned in school that it's a rhombus."  Brian said to me, "Sorry, Lin, you got screwed.  I bought you a rhombus."  (He was referring to my engagement ring.)