Prolixin open bottle dating
If one looks closely at the thick glass in the base of the bottle, one can see that the glass is not quite perfectly colorless, but instead has a slight "straw" or washed out amber tint to the glass (picture of base below).
This is a result of using arsenic and/or selenium as the glass decolorizer.
-There are molded (embossed) "swirls" on the shoulder and upper body of the bottle.
-The glass is clear (colorless) with just the slightest "straw" tint when looking through the thick portion of the base.
The bottle also does not have a ground down surface on the top of the finish.
This yields a "YES" answer to Question #2 and we know that this is a narrow mouth/bore machine-made bottle which very likely dates no earlier than 1905 and probably 1910. (Note: This section of the dating key is a series of independent questions where the answer to any given question is not dependent on the answer to another; a user may view the questions in any order.)In reading through "B", there are a couple other options available to help refine the dating a bit.
Each of the green question hyperlinks result in a pop-up page showing the particular question on the Dating Page; once read it should be deleted to avoid clutter.This page provides some examples of how to use the website (primarily the Bottle Dating pages) to determine the approximate date or date range for various types of bottles made between the early 1800s and the mid-20th century.