Diamonds are not a student’s best friend

For the labtest, I gave my students a small programming task that involved creating a system that catalogued diamonds.

The top row are the Steinmetz Pink, the Millenium Star and the Allnatt. On the bottom row are the Heart of Eternity, the Pumpkin, the Moussaieff Red and the Ocean Dream. Collectively, these diamonds weigh in at over 400 carats, and are worth well over US$100 million.

The students had to implement a Diamond business object, which had a weight property. Here is one student's implementation:

I wonder if those are baby carrots or full grown? Cooked or raw?