The Illinois Watch Company introduced a brand new model of 12-size watch around 1918. The 12-size Extra-thin 1st model movement came in four grades - 17j grade 435, 19j grade 437, 21j grade 438 and the extra-finished 21j grade 439. A non-standard movement, these were factory-cased in fine 14K and 18K cases made by three or four different manufacturers. Many had carving or inlaid enamel ornamentation. Mysteriously, I have not yet found any factory catalogs or period advertising for these complete watches and they were only produced for three years. Production was limited, with only 3,830 movements listed in all four grades (and it is possible that not all were finished). A great many of these lost their cases in the Great Depression. The following list includes available information for over 50 surviving examples, more than half still in their original cases. I do not yet have examples recorded from all production runs and I will continue to add to this list from new examples that come to light. Even from the limited data a trend in case usage is becoming apparent, progressing from the unknown maker-A, to Knapp, to Wadsworth and Solidarity.

grade 435 - 17j 310 produced
grade 437 - 19j 2,060 produced
grade 438 - 21j 1,130 produced
grade 439 - 21j Extra 330 produced
Total production 3,830

Following are the numbers of movements and cases as observed in collections, auctions and sales:

SERIAL NUMBER__GRADE__QUANTITY__CASEMAKER____CASE #__NOTES

3268701-800_______435___100
____3268760________________________maker A______4622____14K
3268801-900_______437___100
____3269857________________________movement only
3268901-950_______435____50
3268951-960_______439____10
3268961-9000______438____40
3269801-900_______437___100
3269901-960_______438____60
3269961-70000_____438____40
____3269979________________________maker A______4523____18K w/enamel trim
____3269983________________________no data

3388351-360_______435____10
3388361-370_______437____10
3388371-380_______438____10

3482001-150_______435___150
____3482018________________________no data
____3482047________________________recased
3482151-2400______437___250
____3482178________________________maker A______4783___18K (scrapped), dial for Tiffany & Co.
____3482194________________________no data
____3482224________________________movement only
____3482245________________________movement only, dial for Tiffany & Co.
____3482298________________________maker A______4842____14K
____3482333________________________maker A______4860____18K for Tiffany & Co.
3482401-480_______438___80
____3482411________________________maker A______7135____18K
____3482424________________________maker A______4737____18K w/ carved edge
____3482458________________________maker A______4538____18K w/ enamel trim
____3482476________________________movement only
3482481-500_______439____20

3650201-600_______437___400
____3650230________________________maker A______7346____14K
____3650347________________________no data
____3650437________________________movement only
____3650511________________________movement only_____________“Marcus & Co” dial
____3650513________________________maker A______7622____18K w/ carved edge
3650601-900_______438___300
____3650623________________________maker A______5449____18K
____3650658________________________maker B______7404____14K
____3761666________________________maker A______5406____“Tiffany” dial
____3650731________________________maker A______5536____14K w/ enamel trim
____3650738________________________maker A______7192____14K w/ carved edge
____3650859________________________maker A_________________18K w/ enamel trim
3650901-1000______439___100
____3650916 ________________________maker A______7454____18K w/ enamel trim
____3650946________________________ ? ______________________14K
____3650958________________________movement only
____3650988________________________Knapp_______52616____18K

3761401-800_______437___400
____3761455________________________Knapp________8369____14K (scrapped)
____3761550________________________Knapp________8386____14K
____3761639________________________Knapp________9030____14K dial for CD Peacock
____3761731________________________Knapp________9720____14K w/enamel
____3761736________________________Knapp________8747____14K
3761801-950_______438___150
____3761882________________________Knapp________8423____14K w/ carved edge
____7761909________________________Keystone_____________g.f.
____3761927________________________Knapp________8726____18K
3761950-2000______439____50
____3761987________________________no data

3885601-86000_____437___400
____3885660________________________Knapp
____3885720________________________Knapp
____3885753________________________Wadsworth__1206110___14K

3904001-400_______437___400
____3904055________________________Elgin Giant__5450871___g.f.__“Bigelow Kennard & Co” dial
____3904138________________________Solidarity
____3904177________________________Wadsworth__7082408_______g.f. Aristocrat w/ carved edge
____3904298________________________Wadsworth__7083060_______g.f. Aristocrat
____3904312________________________Wadsworth__1206161_______14K Aristocrat
3904401-850_______438___450
____3904476________________________Solidarity____553715____14K Aristocrat w/ carved edge
____3904521________________________Wadsworth________________GF Aristocrat w/ carved edge & enamel trim
____3904533________________________no data
____3904553________________________Knapp_______11955____18K w/ enamel trim
____3904629________________________movement only
____3904635 _______________________Wadsworth__1206074____14K Aristocrat w/ carved edge
____3904659________________________movement only
____3904663________________________Solidarity__538019____14K w/ carved edge
____3904717________________________Wadsworth
____3904760________________________Wadsworth__1206050____14K Aristocrat w/ carved edge
3904851-5000______439___150
____3904929 _______________________Wadsworth_1206012____14K Aristocrat
____3904933________________________Wadsworth
____3904936________________________Wadsworth__1206008____14K Aristocrat w/ carved edge
____3904948________________________Wadsworth__7083381____g.f. Aristocrat
____3904995________________________movement only


Administrative Notice:
Thanks to Jerry Treiman for contributing his data to IHC 185 for this project.

Great post and nice work, Jerry. Thanks for sharing all this worthwhile information. 12 size watches are of growing interest to most of us as well. Happy "smaller size" Hunting!

Here is a photo of one of the nicer cases (on a gr.439). This one is made by an as-yet unidentified casemaker who I have designated temporarily as "maker A". Characteristic features (although not unique to this maker) are the shape of the pendant and bow and the nature of the gold mark. Serial numbers are four-digit numbers in the four to seven thousands and are generally stamped in an arc (although individual numbers are upright).

hi

I recently purchased a box lot of watches and found a no name (on the dial) 12size watch. Upon opening the watch I discovered this Illinois serial #3650661 21j Adj movement. Yes it is in a 14K case #7882 with enamel trim. The crown is wrong and the bow is missing, but the case is in very good condition. The watch runs very nicely but the main spring is broken.

The movement