Glass bottles have been around for centuries. It is believed that glass bottles were invented by the Romans in 1AD. Due to the rich history, glass bottles are considered collectible antiques. Normally, the older a bottle is, the more expensive it is, so it is very important to know the correct age of a bottle.
Knowing the age of your glass bottles will help you get a fair deal if you plan to sell them. Pick and place automation could help you make a profit quickly as well. Even if you are not a seller, knowing the age of your glass bottle collection will make you sound more knowledgeable and passionate.
Telling the age of a bottle can be a tricky task, following are some indicators of age that will be helpful as you practice this art.
Marks At The Base
The bottom of the glass bottle will tell you the most about its age. Prior to the mid 19th Century, pontil marks were the signature of glass bottles. A pontil is a rod made of iron that was used to hold the bottle during the manufacturing process. As a result, the rod would leave a ring-shaped mark on the base of the bottle, known as the pontil mark. Pontil mark is an indication that the bottle was mouth-blown.
After the mid 19th Century and early 20th Century, the manufacturing process of the glass bottles became automatic and mouth-blown techniques became obsolete. That is why pontil marks are a clear sign that the bottle belongs to the early 19th Century or before.
In the last hundred and fifty years, most of the glass bottles were produced by blowing molten glass into a mold. The molds were usually made of wood or iron and when the bottle was separated from the mold, a slight seam would stay there. The seam would be visible from the base of the bottle to the mouth or the shoulder.
It is believed that mold seams can tell the age to an extent. The higher the seam, the newer the bottle. Glass bottles made with recent, sophisticated technology do not have any visible seams.
The age of the bottles can also be assessed by looking at the mouth or lip shape of the glass bottle. In the early 18th Century the lip shape of the vessels was extremely rough. By the start of the 19th Century, crude-tapered lips took to the market. By the middle of the century, the lip shape of the glass bottles became more refined.
During the same time double-rounded lips gained popularity. In the second half of the 19th Century, thick and blob-top lips became common which were transitioned into a donut-like shape in the later years of the 19th Century.
The Shape Of The Top
The top of the bottle has many shapes and types. Some of the most famous tops include cork top, crown top, and screw top. Corks have been the most dominant in the glass bottle industry. Cork tops were used mainly by the bottle manufacturing companies of the 18th Century.
Screw tops were invented in the early 1800s. However, screw tops could not gain popularity until the mid-1900s when machine-made bottles started to emerge.
Crown tops led the market mainly during the late Victorian age i.e. 1880s. They were highly popular until the mid-1900s when machine-made bottles took over.
The embossed markings or carved letters show the age and origin of the bottle. They can either be found on the side or on the base of a glass bottle. These embossed markings can be in the form of symbols, signs, words, letters, or numbers. In the past, it used to be so hard to carve out a proper letter on the base of the bottles.
Hence, half-etched and de-formed embossed markings can be an indication of a certain age. Embossing is the most straight-forward way of knowing the age as sometimes the emboss contains the date of manufacturing or the name of the manufacturer.
Collecting vintage glass bottles is a great hobby that gives a glimpse into history. If you are just starting out in the area of glass bottle collection, you need to practice telling bottle’s age a lot. There are many reproductions of the vintage and valuable bottles out there, and sometimes it becomes hard to tell the difference between a real piece and a fake one. It is important to do your research, learn to date the bottles, and try to gain first-hand experience so you are not scammed by a random stranger.