Diamonds – the reflective birthstone for April
Updated: Apr 3
Mineralogy was THAT class. You know the one: the class in your major that starts with 35 people and ends with 10…. The semester you discover yourself reciting facts and figures (or crystal structures and chemical formulas) in your sleep (much to your roommate’s dismay).
For a class that seemed destined to stress us out as our numbers dwindled precipitously before the last drop date, it was actually a lot of fun and I looked forward to each class session (except possibly the test days). I could always depend on the class to provide both knowledge and free entertainment:
· One day someone decided to use water displacement on the halite cube. It melted. Our professor was not impressed.
· HCL, stands for hydrochloric acid. Even at the minimal strength offered in class it will react with calcite, notebooks, fingers and t-shirts.
· Collections of UV fluorescent minerals means sending students into a tiny closet awkwardly in pairs armed with a flashlight.
· I was horribly attacked by a lint ball while trying to learn how to use a microscope. (IT WAS SO HUGE!)
· It is indeed possible to give yourself a migraine with a microscope by switching between plane and polar light too suddenly, too often.
· Green garnets are evil.
· Fluorite is also evil.
· We watched a documentary about blood diamonds and all cried.
· Scratch plates are a true hazard to the safety of fingers. And the idea to use a glass bottle as a scratch plate was about as intelligent as it sounds.
· Our professor (always worried that we as college students were in imminent danger of scurvy) added boxes of tiny mandarins to the timed mineral test. It was a jolt to discover that I was being given a snack for those three minutes!
The class diamond was shown to us somewhere around the mid-semester mark. The build-up was intense. Our professor explained that it had four directions of perfect cleavage (visualize a double pointed pyramid). The hardness is defined as 10 on Moh’s hardness scale. (We were all still a little skeptical of scratch plates after a previous lab week’s crumbling-before-scratching-the-glass fiasco with the garnet.) We were desperate to try out our skills on something as rare and cool as a diamond! Plus, most of us had never seen a real diamond. (One classmate explained vigorously and loudly that we should be prepared to be highly disappointed as her cubic zirconia engagement ring was sure to be MUCH prettier than any lab sample diamond.)
Then the diamond appeared. It was in a cardboard box. Our professor pulled a well wrapped bundle out of the middle of the paper confetti and slowly unrolled the paper. We all leaned in to stare. Tiny, it rattled in a little glass bottle whose yellow screw top was a brighter, clearer color than the greyish-yellow speck of diamond. (It was in a different class that we defined that size as “coarse sand” instead of “prospective mineral sample for today’s lab”.)
“This is our department diamond. Please observe the perfect cleavage planes as you pass it around. Don’t let it out, the department cannot afford another.” *rattle, rattle, rattle* Our professor shook the vial a few more times, as if to wake it up, and handed it to the first person in the row.
It took several minutes and my hand lens, but I would agree. Four directions of perfect cleavage!