You've entered the world of
exonumia, coins struck for a purpose other than legal tender. This piece would qualify as an advertising token; it gives the name and location of a firm, its logo, and a slogan ("Sterling Quality"). It's not a trade token; if it were, it would say something along the lines of "Good For One Spool of Baling Wire," though it's always possible these were redeemable at Sterling Manufacturing for some kind of promotion.
Here's a good place to start:
http://www.tokenandmedal.org/page1/page1.html