This episode shines a light on crystals, and they’re sparkling right back at us! We’ll zoom way in on a diamond to understand the structure that makes crystals special, and hear about some unexpected crystals, too (hint: chocolate chip cookies contain a few different crystals!). Then, we take a look at how crystals form and get their cool colors. Plus, Marc and Sanden hunt down a hoax about Mesoamerican crystal skulls.

And! A mystery sound and a moment of um: why does sugar taste sweet?