The Pen Detective’s Guide, Chapter 3

(This page revised October 10, 2015)

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As noted in Chapter 1 of this series, learning about the pens you collect can be fascinating, and it makes you more able to find those really great pens that others might miss. Part of knowing about pens is knowing when a given pen was made. Being able to tell when a pen was made can help you to identify its maker and what it’s made of. Knowing when it was made can sometimes help you to distinguish between an ordinary pen and a desirable one of the same model. (First-year models are usually more highly sought after by collectors.)

When were these pens made?

Fountain pen Magnifying glass
Fountain pen Magnifying glass

The pens shown above are both easily identifiable as versions of Waterman’s Ideal No 12. (The No 2 nibs they bear are a dead giveaway, as are the numbers on the distal ends of their barrels, but in case neither of these clues is sufficient, you can look it up on a Web page showing how Waterman’s Standard Numbering System worked.) But is one older than the other, and if so which is the older one? And what difference does it make?

Enter the Pen Detective.

How do you date a pen when there’s no apparent way to do so? This is another of those questions that take good detective work to answer. This article offers some advice about dating a pen.

Dates the Manufacturer Gives You

The first and easiest way to date a pen from the manufacturer’s dates is to be looking at a Parker pen with a date code on it. With Parker’s date codes, you can pin a pen to a specific three-month period. Date codes were used from 1933 to c. 1955, and they have again been in use from 1980 to the present.

Fountain pen Magnifying glass
Fountain pen Magnifying glass

Pens Without Date Codes

The phrase “pens without date codes” covers the vast majority of all the pens ever made. In the case of the Waterman No 12 pens shown at the beginning of this article, it’s still relatively easy. Along with many other early manufacturers, Waterman kindly imprinted its pens with patent dates until the 1930s. They would have been kinder yet to give us the actual patent numbers, but we work with what we have; and in one case, that of early Sheaffer Balances, the actual design patent number (U.S. Patent No D78,795) is given as the last line of the barrel imprint.

Patent dates do not indicate when a given pen was manufactured; they reflect the dates of issuance for the most recent patents incorporated into the pen. When we look at the two Watermans shown at the beginning of this article, we find the following dates:

Based on the “latest patents” criterion, it’s clear now that the lower pen is the older of the two. What can the two pens’ patent dates tell us about the pens themselves?

Patents are often issued months, or even years, after the features they cover are implemented. You have probably seen pens with imprints reading Patent Applied For or Patent Pending. Because filing a patent application affords some protection and receiving notice that your patent is pending steps up the level of protection, many manufacturers will start using the features in question before the patents are finally issued. But a patent date cannot appear on a pen until the patent is issued; therefore, the upper pen was made no earlier than August 4, 1903. (The patent in question is U.S. Patent No 735,659, and it concerns the shape of the feed, which made it more difficult for the user to get inky fingers.) The end date for this pen would be around the time when Waterman stopped using slip caps in about 1912 or 1913.

We have a good start date for the older pen, but what about an end date? For that, you have to know a little about the features of the pen. In this case, again, it’s the feed. Waterman patented its famous Spoon feed in 1898 (U.S. Patent No 625,722). The feed in this pen is not a Spoon feed; it's the original design that is covered by the patents whose dates are on the pen (U.S. Patents Nos 293,545 and 307,735). From this we know that the pen was made before 1898, and probably a couple of years earlier. To date the pen more closely than that requires the skills of an expert, and the one I consulted — never be afraid to ask for help from someone who knows more than you do — told me that the pen was probably made in 1895 or 1896. Does this matter? To a Waterman collector, it can be important as that collector tries to put together a representative collection. It can matter to a user, too, because pens that were made before the Spoon feed came into use are more likely to throw blots than are later pens.

It’s also possible to infer dates with relative accuracy, especially given the distance of a century or so, by using a PATENT APPLIED FOR or PATENT PENDING imprint. If you can find another specimen of the pen in question, one that bears the date of issuance for the patent that was in process on your pen, you can search out the patent (see Chapter 1) and learn when it was issued — and also when the application was filed. Your pen was almost certainly made between the application and issuance dates, with a little possible overlap at the end due to the time it would take to get the imprinting dies changed. This method will usually yield a period of one or two years in which your pen was made.

Design Changes

Let us now look at another interesting example, the ubiquitous Esterbrook Model J. It turns out that there are at lease five subtly different versions of the J, only the first and last of which can be dated to specific years of introduction (1944 and 1948, respectively). The other three versions were phased in and out, one after another, as Esterbrook kept tweaking the design during that five-year period. The easiest way to classify these pens is by examining them carefully. Here is a list of the five versions, in chronological order:

  1. The original 1944 version is a single-jewel pen; i.e., it has a cap jewel but no barrel jewel. (The end of the barrel is simply cut off flat.) The cap jewel screws into the cap crown and has three ribs running across it. On the underside of the jewel, where you cannot see them without disassembling the cap, are six tabs that fit into corresponding notches around the edge of the hole in the center of the clip washer. If the pen hasn’t been disassembled and put back together wrong, the ribs run from front to back as a continuation of the clip, which also has a three-rib pattern. There is no Esterbrook imprint on the clip.

    Fountain pen Magnifying glass
  2. The second version looks like the first, but its jewel is pressed and cemented into a plastic bushing that is buried under the clip, not screwed in. This jewel does not come out easily.

  3. The third version has a different jewel. Gone are the ribs, to be replaced with a plain round boss.

  4. The fourth version looks like the third, but it now has an Esterbrook imprint on the clip.

  5. The final 1948 version is like the fourth, but it has gained a barrel-end jewel and tassie to make the pen’s overall look more stylishly symmetrical from end to end.

    Fountain pen Magnifying glass
    Fountain pen Magnifying glass

There are several other examples of dating by design changes in the articles listed below. Some can provide very specific years, others are less specific due to the frequency (or lack thereof) of design tweaks.

Material Changes

Chapter 2 of this guide looks at materials in pens. You can use materials to help you date a pen. Here is a short list of some specific dating aids:

  1. During the first year of production (mid-1948 to mid-1949), the sac guard was made of polished aluminum, and the text imprinted into it was filled with black paint. This guard screwed onto the plastic connector that joins the front and back halves of the pen.

  2. During the second year of production, the sac guard was made of chrome-plated metal, not filled with black paint, and was still threaded.

  3. From the third year of production until the introduction of the Mark II version in 1962, the sac guard was made of brushed stainless steel and was no longer threaded, instead relying on a press fit.

  4. Beginning with the Mark II, the sac guard was made of lightly polished stainless steel and no longer had a plastic end cap.

Knowing these materials and their dates, suppose you are looking at a pen whose barrel bears a date code of 4Q1948 (the number 8 with no dots). This pen should have an aluminum sac guard. If the sac guard is plated, it’s a second-year guard; but it will fit the first-year connector, so the pen’s guts could be either first or second year. A brushed or polished stainless steel sac guard tells you without ambiguity that the barrel has been fitted to a later set of internals.

Other Chapters in the Pen Detective’s Guide

The information in this article is as accurate as possible, but you should not take it as absolutely authoritative or complete. If you have additions or corrections to this page, please consider sharing them with us to improve the accuracy of our information.

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