MaterialsScience2000

I love seeing the crystal grains develop as the acid etches the metal surface. It's just gorgeous.

The eight-and-a-half-minute video above shows the preparation of a few different samples, some of which show crystals large enough to be seen by the human eye as well as a few samples that have been etched through natural processes over time.

MaterialsScience2000 has ten total videos posted, and many of them are worth a watch, including a thorough explanation of the tests being preformed. Check out these, too...