Another exception example is that the bottles for expensive, low production liquors e. Specialty bottles include a significant number of bottles in the following categories: Many specialty bottles were imported from Europe, though that fact may be at times hard to impossible to ascertain. Specialty bottles can be, of course, occasionally found on historic sites usually fragments, but occasionally intact but can rarely be used to help date the site because of the diagnostic problems and deposition lag issues noted above.

Having stated the above, there are still many diagnostic features or characteristics that provide a high probability of both dating and typing a bottle with some precision.

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A key concept in historic bottle dating is the high probability i. The general probability estimates noted on this website are based on a merging of reliable references with empirical observations made by this site's affiliated consulting experts see the About This Site page and the author who have been students of historic bottle dating and identification for many years. N otes on embossing, labeling, and existing research. Raised embossing and when present, paper labeling on a bottle can frequently provide important details to refine the probable manufacturing date range if information exists for the company that either manufactured the bottle i.

For example, the early mineral water bottle pictured here is known to date between based on the information provided by the embossing company name embossed on the pictured side and the glass maker - Union Glass Works - embossed on the reverse and complimentary research done by collectors Markota Researched historical information of variable depth and quality exists for thousands of different - typically embossed - bottles.

Published works generally cover either a particular city, region, or category of bottles. Quality examples of references within each of these three categories are, respectively, Gordon Pollard's book on Plattsburg, NY bottles Bottles and Business in Plattsburgh, New York: See the References page for more information. For a large majority of embossed and unembossed bottles, however, there is little or nothing formally published on the details of their origins. Only a relative few geographic areas or areas of collecting interest have received more than cursory historical treatment and the majority of this is due to the efforts of collectors.

Time has taken its toll on records, of course, but much of what happened in the past was simply not documented well or at all as with most endeavors of common people in the past. As noted in Munsey's book, " When it comes to methods of dating bottles As Munsey also notes - " Most of what is used today to date bottles Still all true today.

This body of information will be utilized and extrapolated to make dating and typing estimates for the majority of bottles for which there is either no specific company or glass maker information available or such is not possible to determine because the bottles are unmarked i. To the authors knowledge, the first and only serious attempt at using a key to date American bottles was done in a Historical Archaeology journal article entitled A Dating Key For Post-Eighteenth Century Bottles by T.

Stell Newman Newman Newman's key made a noble attempt at simplifying bottle dating, but is weakened by the fact that the subject is much too complex to be conducive to such a simple approach by itself. Also, the format and space constraints of a journal article do not allow for the elaboration and illustrations necessary to make a key function fully Jones b. Newman wryly recognized all this with his reworking of an old saying: A pdf copy of Newman's article is available now courtesy of the SHA by clicking on this link: This website is designed to have the informational depth, pictures, and illustrations necessary to solve the problems of the Newman key though his warning still holds though hopefully less so.

This entire website is essentially a key to the dating and typing of bottles.

BOTTLE BASICS

Before jumping into the key, it must again be emphasized that no single key can get a user to an absolutely precise date for any bottle. The best the following key can do is get a user to a reliably close dating range estimate. Other information on this website usually must be reviewed to fine tune the information about a specific bottle. In addition, other references beyond the scope of this website usually must be consulted to get as complete of a dating and typing story as is possible for any given bottle.

Keep this all in mind as you progress through the key which follows and on into the other website pages Starting with Question 1 , follow through the questions as suggested.

There is frequent hyper-linking between the diagnostic characteristics and terminology listed on this page and other website pages. This is done to allow the user to get more information or clarification as they proceed through the key. Pursue these links freely since they will take a user to more details on bottle dating and identification and hopefully add to the users knowledge and understanding about the bottle being "keying out".

When a dating sequence dead ends, it will be noted and other website pages suggested and hyperlinked for the user to consult. The three questions found on this page below answer several basic questions about a given bottle. Answers to these questions will then direct a user to one of the two additional dating pages which are extensions of this key for the two major classes of bottles - mouth-blown bottles and machine-made bottles. Read the questions - and accompanying explanations and exceptions - very carefully as the correct answer is critical to moving properly through the "key. This page guides a user through the key for seven different type and age bottles with several being side-by-side comparisons of very similar bottles of different eras.

This page also shows how other portions of this website can provide information pertinent to the bottle in question. See the About This Site page for more information about the author and contributors. For brevity, most of the specific references are not noted in the key's narratives. They are noted on the other website pages which expand on the information summarized in the key.

If you know your bottle is machine-made click Machine-Made Bottles to move directly to that page.

If you know your bottle is mouth-blown aka hand-made click Mouth-blown Bottles to move directly to that page. If unsure about what embossing or vertical side mold seams picture below are, click on Bottle Morphology to see this sub-page for a illustration and explanation of these and many other key bottle related physical features.

Return back to this page by closing the Bottle Morphology page. Vertical side mold seam on the neck of a beer bottle ending well below the finish, indicating that it was at least partially handmade - ca. YES - The bottle has embossing or visible vertical side mold seams somewhere on the body between the heel and the base of the finish or lip.

A bottle may have mold seams but no embossing, but all embossed bottles were molded and have mold seams even if they are not readily apparent. This bottle is either free-blown , "dip" molded , or was produced in a "turn-mold" aka "paste-mold" where the side mold seam is erased during manufacturing. A "NO" answer is much less likely than "YES" for this question as a very large majority of bottles made during the 19th century and virtually all made during the first half of the 20th century were mold blown resulting in mold seams; see the note below.

A low probability though possible "NO" alternative is that the user has an unembossed, molded bottle with no visible vertical side mold seams. This can be due to one or a combination of factors including post-molding hot glass "flow" masking the mold seams, fire polishing of the bottle body, or atypically good mold fitting precision.

If necessary, look very closely at the bottle shoulder - the best location to see vertical side seams on mouth-blown and most machine-made bottles - in good light with a hand lens to see if there is at least some faint evidence of where the mold edges came together. Often the vertical side mold seams are evidenced by very faint changes in glass density in lines where one would expect mold seams to be.

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. The concept is that the higher the side mold seam on the bottle the later it was made - at least in the era from the early to mid 19th century until the first few decades of the 20th century. Mold Seams of Bottles" chart Figure 9. Kendrick's explains in the text pages that It is true that the mold seams can be used like a thermometer to determine the approximate age of a bottle. The closer to the top of the bottle the seams extend, the more recent was the production of the bottle.

The chart accompanying this statement notes that bottles made before have a side mold seam ending on the shoulder or low on the neck, between and the seam ends just below the finish, between and the seam ends within the finish just below the finish rim top lip surface , and those made after have mold seams ending right at the top surface of the finish, i. Although there are examples of bottles having mold seams that fit these date ranges properly, the issue of dating bottles is vastly more complicated than the simple reading of side mold seams.

If it were that simple much of this website would be unnecessary! For example, the process that produces a tooled finish frequently erases traces of the side mold seam an inch or more below the base of the finish whereas the typical applied finish has the seam ending higher - right at the base of the finish Lockhart et. The reason this is noted here is that the concept keeps popping up in the literature of bottle dating and identification ranging from Sellari's books Sellari For a broader discussion of this subject see Lockhart, et al.

If unsure about what the lip , rim , or finish of a bottle is, check the Bottle Morphology sub-page. If you need more information on this diagnostic feature - including various images - click the following link: This is a "machine-made" bottle or jar and will also usually have a highly diagnostic horizontal mold seam just below the finish that circles the neck.

Dating Antique Bottles

The picture to the left shows both of these mold seams click to enlarge. If your bottle fits this description, click Machine-made Bottles to move to the related webpage which allows the user to pursue more information on bottles produced almost totally in the 20th century by some type of automatic or semi-automatic bottle machine. The vast majority of U. If your bottle has a ground rim or lip, more information can be found at the following link: The following is a discussion of the most common exceptions to the side mold seam "rule" describing a few types of machine-made bottles on which the vertical side mold seams do not quite reach the top edge of the finish making them possible appear to be mouth-blown.

Fire Polishing - Occasionally encountered machine-made bottles may have fire polished finish rims - a process which eradicated evidence of the neck-ring mold seam on the rim of the bottle. These bottles will not have the side mold seam proceeding from the upper finish side over and onto the rim itself. Ostensibly this was done to remove the mold seam "bump" that was sometimes left by earlier machines - an action which may have helped facilitate better sealing with crown caps, screw-thread caps, or similar closures which sealed on the rim of the finish. These bottles will, however, have the vertical side mold seam progressing all the way to the very top of the finish side, just not onto the rim.

They will also have other machine-made characteristics as described on the Machine-made Bottles page. In the experience of the website author, these machine-made bottles are rarely encountered and likely a function of early machine-made wares to s that had less precise mold fitting and resulted in the need for fire polishing to enable proper closure. These cheaply produced bottles primarily date from the s to s era when bottle machines were rapidly dominating the market and are reflection of the economic pressures that eventually overwhelmed factories that still used older methods Wills ; Boow The image to the right is an example of a burst-off finish on an English ink bottle made during the early 20th century.

Mouth Blown Dating

The quick burst-off blowpipe removal method was likely utilized from the earliest days of glassmaking in the U. The blower gathered the melted glass, rolled it on a marver, blew into it slightly, then dropped it, in a long, purse-shaped, glowing lump, into the open mould. This was immediately closed by the boy; then the blower blew until a bubble, pushed up on the top of the mould, expanded to the size of a football, and to the thinness of the thinnest transparent film, and finally burst with a loud pop, flying into shreds of tinsel, light as feathers.

The mould was then opened and a caster-vial with figured sides was exposed As noted above, when a bottle was burst-off from the blowpipe an obvious hazard for the mold operator!

The residual glass on the end of the blowpipe called the "moil" was beat off the tip to keep the blowpipe working properly; this is shown in the film clip linked below. The remainder of the thin fragmented bubble glass scattered around the immediate work area though some occasionally fell into the bore of the bottle adhering to the upper neck and even base of the bottle. The image to the left shows fragments of very thin glass adhering to the inside of the neck below the blowpipe removal point and applied finish.

The view to the right click to enlarge both images shows similar fragments inside the bottle on the base. Click base fragment view looking down the bore to see the glass fragments inside on the base looking down the neck of the bottle. This feature could only be caused by the burst-off fragments becoming "stuck" to the hot glass immediately after the bubble burst and is proof that the burst-off method was used for blowpipe removal. Sometimes such pieces are also seen imbedded on the outside of the body or base of the bottle indicating that some could fall into the mold and be picked up by the next bottle blown.

The bottle illustrated here is a blob soda which is embossed with J. It dates from the mid s to the s based on these being found both with and without iron pontil scars indicating manufacturing during the transition time from pontil rods to snap tools von Mechow Click full sized view of this soda bottle to see such. All of these bottle photos courtesy of Richard D. The link below is to an amazing early 20th century film clip of a mouth-blown "shop" blowing bottles.

The overall process of blowing is described on other website pages, though of particular note here is that the gaffers in this shop are using the burst-off method to detach the blowpipe. One can almost hear the "pop" as described by Trowbridge above!