I googled and found an article that might be of interest to you, since the token is commemorating the 25th anniversary of Skelgas

In part, it says "Skelly Oil entered propane marketing in 1928 with the introduction of Skelgas. Like Phillips, Skelly developed many of the storage and delivery system principles that then entire industry would adopt, and in later years offered a complete line of propane appliances for use with the products."

Here's the whole article:
http://www.collectorcafe.com/article_archive.asp?article=10&id=1510