Classic watches, watchmaking, antique tools, history, vintage ephemera and more!
Learn about mechanical timepieces and how they work, the history of the American watch industry and especially all about the Elgin National Watch Company! Check back for new content daily.
Although this is technically a blog, the content is not generally in a time-based sequence. You can find interesting items throughout. Down the page some is an alphabetical word cloud of keywords used here. A great way to dig in is to look through those topics and click anything you find interesting. You'll see all the relevant content.
Here are a few of my favorites!
There are some large images on some posts, so that might impact your load times, bit I think you will find it worth the wait. Thanks for visiting!
The watch is a nice 17 jewel Hamilton. It was brought in Clark's Jewelry (formerly Overjourdes' when my Grandfather owned it) in Coeur d'Alene.
I'm not sure of the best way to present things like this (ordinary web site? Blog? Online document?). There are a lot of choices these days so I may use more than one now and then, to see what works best.
Anyway, to get started, here is some information on watch crystal codes.
Watch crystals are categorized using a cryptic code of letters and numbers the meanings of which may seem completely arbitrary at first. It may surprise some, but there are actually meanings to these codes.
Firstly, the basic shape of the crystal is given by a letter. The following letters are used in one common code system, used for G-S Flexo crystals.
|R||Rectangular with cut corners|
|T||"Tonneau", two straight, parallel sides (short) the other two (long) convex|
|Q||Square with cut corners|
|C||"Cushion", four convex sides|
|D||Diamond or an elongated octagon|
|Q||Square, cut corners|
|V||"Rococco", concave corners|
|Y||Similar to T but with convex short sides instead of long sides|
|Z||Rectangular with concave sides|
|F||"Fancy" - any other shape, generally irregular such as hearts|
These letters (one, two or there) are followed by a number indicating the specific crystal.
Here's a few examples:
MT2005 - A tonneau crystal, not flat but curved, number 2005
MS1975 - A square crystal, curved, number 1975
CMS2050 - A Square crystal, curved, and cylinder
There are a few other labels, types and designators found on watch crystals such as "Durex", which is a extra thick. Also, lines of plastic crystals ("unbreakable") frequently prefix a 'P' to the entire code. Watch-Craft and Rock-Craft are quite common crystals these days, but they use shape codes different from the above.
This is not the only crystal designation system. Many manufacturers used their own systems which were either completely different, or included additional shape codes. This is inconvenient, but to me it is one of the fascinating things about vintage watches. These systems where early attempts at standardizations that we take for granted today. The systems are cryptic because they were created in a time long before computers. At that time, having any system at all was a major selling point for watch companies, watch parts houses and suppliers ("jobbers").
Finding the right crystal for a particular watch can still be a challenge even with this system. But that's another topic...
One of a series of little biographies or Elgin Watches
- ► 2017 (108)
- ► 2016 (465)
- ► 2015 (452)
- ► 2014 (291)
- ► 2013 (281)
- ► 2012 (406)
- ► 2011 (135)
- ► 2010 (75)
- ► 2009 (96)
- ▼ July (4)