Dating bottle glass
One can find quite a bit of information on my web site and across the Internet about dating bottles based on whether the mold seam goes up and over the lip or if the bottle has a 'pontil' on the base. Even given these descriptions beginning often mistake a machine made Owen ring on the base of a bottle with a pontil. Specifics on what a pontil looks like or how to tell the age based on the mold seam can be found in Bottle Basics. While these two characteristics are often a strong clue to age, readers will be further helped by developing an understanding how the various categories of bottles changed over time. These diagrams should help clarify age differences based on both form and function.
Dating Antique Bottles
Dating antique bottles requires knowledge of the evolution of bottle technology and the ability to research manufacturers and bottling companies. Although glass bottles have been made for a few thousand years, it was not until the 19th century that bottle use became common, coinciding with the industrial revolution. By the midth century, embossed lettering and marking on bottle bodies and bases, denoting manufacturers and products, made more precise dating possible.
In addition to technology, products and manufacturers, certain types of glass colors will also aid in dating. Look for mold seams. The earliest bottles were hand-blown by a glassblower with a blowpipe and lack seams. Is the bottle highly symmetrical, but lacking mold seams? This type of bottle was probably dip-molded and dates after circa Is the base indented with an irregular to round pontil scar? This, and no mold seams, is another indication of a hand-blown bottle. A pontil rod held the nearly molten bottle during the final stages of manufacture.
The scar was left when the pontil was detached from the bottle. Look for side mold seams. If the seams disappear in the neck, the bottle was probably "blown-in-mold" and dates circa to early s. Is a pontil mark present along with disappearing side mold seams? This bottle probably dates circa to Do the mold seams disappear in the neck, but the bottle lacks a pontil mark?
Blown-in-mold bottles without pontil marks date circa s to s. Do the mold seams go all the way from the base to the lip? This is a machine-made bottle and dates after Look for a "suction" scar on the base. This will be shallower, wider and more perfectly circular than a pontil mark. Bottles with suction scars were made in an Owens Automatic Bottle Machine and date after The Owens machine revolutionized the bottle industry. Check for lack of bubbles and uniform glass thickness.
This is another indication of a machine-made bottle. Is embossed lettering present? Most bottles with embossed lettering date from the late 19th century and later. Lettering on the body will give clues to the contents and lettering on the base will give clues to the manufacturer. Both require more specific research to refine the bottle's date beyond observation of technology. Is the bottle machine made and aqua- or light green in color?
Aqua glass typically dates from the late 19th century to the s. Does the bottle appear light purple in color? Bottles with a purplish or amethyst hue are made from manganese dioxide glass and date circa to The glass turns purple when exposed to UV light. Keep in mind that older technology often persisted and some bottles date later than you might think. For example, glassblowers still make hand-blown bottles today.
Also keep in mind that bottles could have been used and refilled multiple times. Recycling was very common until the midth century. Do not estimate a bottle's age by its shape. Many identical shapes persisted through time and others were brought back for nostalgia and made common again. John Peterson published his first article in Having written extensively on North American archaeology and material culture, he has contributed to various archaeological journals and publications.
Asymmetry is an indication of a hand-blown bottle. Bottles Circa to Look for side mold seams. Post Bottles Do the mold seams go all the way from the base to the lip? Is the lettering applied and in color? These bottles date after Dating Bottles by Color Is the bottle machine made and aqua- or light green in color? Is the bottle colorless? Machine-made colorless bottles date after Tip Keep in mind that older technology often persisted and some bottles date later than you might think.
Warning Do not estimate a bottle's age by its shape. About the Author. Related Content. How to Date Atlas Jars. How to Date Kerr Jars. How to Identify Old Bottles. How to Identify Antique Glass Bottles. How to Make Glass Bottles.
In reading through "B", there are a couple other options available to help refine the dating a bit. If one looks closely at the thick glass in the base of the bottle, one . Bottle dictionary, marks, identification, dating Old Glass Bottles, Vintage Bottles, Antique Old bottle styles Antique Glass Bottles, Bottles And Jars, Vintage Jars, .
Also included are marks seen on other types of glassware including tableware and industrial glass items such as railroad lantern lenses. Entries on some of the more commonly encountered brand and company names for instance, Bromo-Seltzer seen embossed on bottles are also included, as I frequently get questions about them. This is a typical example, as seen on the bottom of an emerald green bottle with a date code of It was made at their main glass plant plant 7 located at Alton, Illinois. What is glass??
As Berge noted in referring to bottles, the "
Bottle Dating. Bottle Dating:
Glass Bottle Marks: Glass Manufacturers’ Marks
Dating antique bottles requires knowledge of the evolution of bottle technology and the ability to research manufacturers and bottling companies. Although glass bottles have been made for a few thousand years, it was not until the 19th century that bottle use became common, coinciding with the industrial revolution. By the midth century, embossed lettering and marking on bottle bodies and bases, denoting manufacturers and products, made more precise dating possible. In addition to technology, products and manufacturers, certain types of glass colors will also aid in dating. Look for mold seams.
DATING BOTTLES BY THEIR TOPS AND BASES
This webpage is intended to help novice collectors and non-collectors better identify, describe, and date the bottles they encounter. Bottle dating is approximate and just intended to give a relative placement in bottle making history. Painter seam stops below lip common on sodas and beers image supplied by Harry Pristis s machine made crown top seam runs to top of bottle common on sodas and beers - Preset machine made metal cap top seam runs to top used a metal cap with twisted wire seal common on medicines s - s. Baltimore loop looks like blob top on outside inside of mouth has an ring shaped depression seam ends below lip used on beer and soda bottles. Hutchinson stopper seam stops at lip found on Hutchinson type sodas used a spring loaded wire and rubber seal. Flat Tooled uniform shape, no drippy bottom seam stops part way up neck circular tool marks often seen around neck inside of neck is smooth. Tooled Ring uniform shape, no drippy bottom seam stops part way up neck circular tool marks often seen around neck. Painter seam stops below lip common on sodas and beers image supplied by Harry Pristis.
One approach to helping beginner identify their old bottles involves show them the bases of old bottles. The picture below at the left shows an iron pontil on the base jof a historical flask circa
.tips on antique bottles