Dating old ink bottles
Collectors also put a lot of physical effort into expanding their collection.
Digging into the Earth has procured vintage bottle finds for experienced collectors.
However, as noted on the one of the websites below, "one of the longest running "myths" in the world of bottle dating is that the side mold seam can be read like a thermometer to determine the age of a bottle." While the height of the shoulder seam is important information, it must be placed in the proper context of other characteristics of the bottle.
Bottles in the period of 1890 to 1910 were made by a combination of techniques ranging from being blown in a mold by hand with the top hand-finished, to machine made bottles that had minor hand finishing of the top.
Among hand made bottles, certain techniques for hold and gathering the glass changed over the time.
The most important identifying feature of the antique bottles is the pontil or scar, on the base of the bottle.
These scars were made when the glass tipped pontil rod (which is used to hold molten glass while it is worked) was removed.
Pontil scars are generally found on utilitarian bottles until about 1870.