The word used to refer to the material with which the artist works is

put in the 2 images that way we can see it

explain: well re read it 5 times that way if it makes since then its your answer if it doesn't then its not right

your word would be isle.

isle is an island or peninsula especially a small one.

if you add the letter "a" you get aisle, which is a passage between 2 rows of something like chairs, shelves, or something else.