Eric marks dating
The diamond/oval/I mark is by far the most common identification mark on glass containers found in trash dump sites in the United States from the 1930s, 1940s, and 1950s.
(The second most common mark encountered is probably that of the Hazel-Atlas Glass Company.) Owens-Illinois took over operation of the Hemingray Glass Company factory, located in Muncie, Indiana, in 1933.
Base of Yacht Club Beverages ACL soda bottle, bearing 1966 date code along with older mark.
(Photo courtesy of Taylor Mc Burney) " data-medium-file="https:// data-large-file="https:// class="wp-image-1921 size-large" title="Base of Yacht Club Beverages ACL soda bottle, bearing 1966 date code along with older mark.
Illustrated among the pics on this page is the base of a bottle made at the Columbus, Ohio facility (plant #18) with a date code of “7” which in this case probably stands for 1937.
I don’t know how late the word “OWENS” was embossed as a trademark on the base of those medicine bottles.
Also, there are several posts (scattered through the comments farther down on this page) where we have discussed this question.
You can find more info on those bottle base variations by searching the internet with the phrase “liquor bottle permit numbers”.Owens-Illinois continued to have the great majority of insulators marked with the “HEMINGRAY” brand name, with very few exceptions in later years.Other brand names used by O-I on insulators include “Lowex” and “Kimble“.However, there are some exceptions to this general rule, and single-digit date codes were also used in later decades along with the later “I inside an O” mark (but without a period placed to the right of the code).Most bottles from the late 1940s into the 1950s and 1960s have two-digit date codes.