Selenium is the 34th element. See the blog post, Tones of Selenium, for more information.

Selenium

Angstrom	Nanometer (rounded)	Color	Hertz	Note	Hertz
6055.84	601	mid violet	450.24	A4	440
5227.53	523	mid blue	521.58	C5	523.251
4730.78	473	mid green	576.35	D5	587.33
4180.9	418	orange	652.16	E5	659.255

violet

blue

green

orange

scale

improv

full chord