Do you remember the movie The Dark Crystal? It is one of my favorites, so of course I introduced it to my kids. And the awesome thing, when my youngest is asked what the shape in the picture above is, she instantly & proudly announces “crystal shard” haha! I do explain to her, that is a good answer because the crystal shard is in the shape of a diamond. So the shape is actually a diamond, of which the crystal shard would be an example! Cracks me up!