Rhenium is one of the rarest elements in the earths crust, and has one of the highest boiling points at an estimated 5873K. Ever wonder what it looks like under the microscope?
Polarized light microscopy brings out incredible colors in chemicals. Have a look at Bromine under the microscope.
Holmium (a metal) looks fairly interesting by polarized light microscopy.
Resorcinol is a benzenediol used in some chemical and medical fields; Have a peek at it under the microscope.
Have a peek at Menthol, commonly used as a local analgesic under the microscope.