Crossword Genius

An element used in painting? (6)

Ross

I believe the answer is:

iodine

I'm a little stuck... Click here to teach me more about this clue!

This could be a double definition.

'an element' is the first definition.
(I know that iodine is a type of nonmetal)

'painting?' is the second definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I can't see?

'used in' is the link.

Can you help me to learn more?

(Other definitions for iodine that I've seen before include "Element, atomic number 53" , "Element used in medicine, photography and dyes" , "Black/violet element" , "Black crystalline element" , "Disinfectant made from seaweed" .)

I've seen this clue in the Evening Standard.
Want a hint initially instead of a full solution? Install my app