It does not attempt to address the dating of "specialty" or imported bottles made during that time, though much of the information found on this website is pertinent to these items to varying degrees. For this website the distinction between the two categories is related to the varying time frames that different glass making techniques were used for for the two classes of bottles.
Click on to view the portion of the Glossary Page that covers these subjects.
This site instead attempts to help the user determine some key facts - approximate age & function - about any given utilitarian* bottle/jar based on observable physical characteristics.
Empirical observations indicate that Canadian-made bottles very often followed similar glassmaking technique and process chronologies making much of the information applicable to Canadian made bottles. If using this site for the dating or typing of a known or likely Canadian-made bottle, keep this in mind as the reliability of the information may be reduced. The title of any given page gives the predominant theme of that page and would be the first place to start when pursuing information on that particular subject.However, the process of bottle identification and dating is quite complex with many exceptions; thus, the need for many web pages covering a lot of descriptive information.The author created this website as a BLM employee and continues to update and enhance the site in retirement as a volunteer.This website now has a permanent home courtesy of the Society for Historical Archaeology (SHA). This entire website is essentially a "key" - albeit a complex one - to the dating and typing (typology) of historic bottles.This bottle is an Owens-Illinois Glass Company produced beer bottle made in 1941 by the Oakland, CA. If you are attempting to estimate the approximate manufacturing date - or age - of a particular bottle (or significant sized fragment) the first page to visit would be the Bottle Dating page and its related sub-pages.These pages lead a user through a series of questions about the physical - or morphological - characteristics of historic bottles which help to narrow down the age of an item.▪ Field archaeologists trying to identify and date bottles or bottle fragments which are found during cultural surveys and excavations in the United States; ▪ Educators dealing with the subject of historical archaeology; and ▪ Collectors and the general public trying to date a bottle, determine what it was used likely for, and/or begin their search for information dealing with the fascinating world of historic bottles.Some of the embossed markings on the bottle base above are a great information source for 20th century bottle identification; some are meaningless.A listing or "map" of all the main subject pages and connected sub-pages found within this website is found at the following link Website Map.Use that page to get a feel for the structure of this website and to access any of the other web pages.