A Guide to Illinois Watch Co. size 12 watches, Grade 525.
Run.
Date
From
To
Total
H/O
Jls
Adj.
Run.
Date
From
To
Total
H/O
Jls
Adj.
1
1921
3,869,251
3,869,300
50
O
17
Adj.
21
1926
4,825,001
4,826,000
1,000
O
17
3 Pos.
2
1922
4,082,601
4,082,700
100
O
17
Adj.
22
1926
4,827,001
4,828,000
1,000
O
17
3 Pos.
3
1922
4,082,701
4,083,000
300
O
17
3 Pos.
23
1926
4,839,001
4,840,000
1,000
O
17
3 Pos.
4
1923
4,184,001
4,185,300
1,300
O
17
3 Pos.
24
1927
4,855,001
4856000
1,000
O
17
3 Pos.
5
1923
4,185,301
4,186,000
700
O
17
3 Pos.
25
1927
4,872,001
4,873,000
1,000
O
17
3 Pos.
6
1923
4,270,001
4,271,000
1,000
O
17
3 Pos.
26
1927
4,881,001
4,882,000
1,000
O
17
3 Pos.
7
1923
4,345,001
4,346,000
1,000
O
17
3 Pos.
27
1927
4,890,001
4,891,000
1,000
O
17
3 Pos.
8
1923
4,423,001
4,423,300
300
O
17
3 Pos.
28
1927
4,903001
4,904,000
1,000
O
17
3 Pos.
9
1923
4,423,301
4,424,000
700
O
17
3 Pos.
29
1927
4,905,001
4,906,000
1,000
O
17
3 Pos.
10
1923
4,449,001
4,450,000
1,000
O
17
3 Pos.
30
1927
4,912,001
4,913,000
1,000
O
17
3 Pos.
11
1925
4,573,001
4,575,000
2,000
O
17
3 Pos.
31
1927
4,922,001
4,923,000
1,000
O
17
3 Pos.
12
1925
4,618,001
4,619,000
1,000
O
17
3 Pos.
32
1927
4,931,001
4,933,000
2,000
O
17
3 Pos.
13
1925
4,658,001
4,659,000
1,000
O
17
3 Pos.
33
1927
4,946,001
4,947,000
1,000
O
17
3 Pos.
14
1926
4,676,001
4,677,000
1,000
O
17
3 Pos.
34
1927
4,956,001
4,958,000
2,000
O
17
3 Pos.
15
1926
4,708,001
4,709,000
1,000
O
17
3 Pos.
35
1927
4,967,001
4,968,000
1,000
O
17
3 Pos.
16
1926
4,723,001
4,725,000
2,000
O
17
3 Pos.
36
1927
4,976,001
4,978,000
2,000
O
17
3 Pos.
17
1926
4,739,001
4,740,000
1,000
O
17
3 Pos.
37
1927
4,986,001
4,987,000
1,000
O
17
3 Pos.
18
1926
4,751,001
4,752,000
1,000
O
17
3 Pos.
38
1927
4,989,001
4,990,000
1,000
O
17
3 Pos.
19
1926
4,774,001
4,775,000
1,000
O
17
3 Pos.
39
1927
4,995,001
4,996,000
1,000
O
17
3 Pos.
20
1926
4,812,001
4,813,000
1,000
O
17
3 Pos.
40
1928
5,006,001
5,007,000
1,000
O
17
3 Pos.
                  Total
41,450
 
Name
H/O
Estimate
Name
H/O
Estimate
The Marquis
17 Jewels O.F.
3,800
The Marquis Autocrat
17 Jewels O.F.
37,600
Illinois Watch Co. Aluminum
17 Jewels O.F.
50
Spaulding & Co.
17 Jewels O.F.
100
Serial numbers used on this page by the kind permission of  
Russell W Snyder
Grade 525 Movements found to date.
Grade 525 runs.
Last update 03/22/2016.
Grade 525,
17 ruby and sapphire jewels adjusted to 3 positions, manufactured from 1921 to 1927 a total of 41,450 movements in 40 runs make up this grade.
Model 3XT open faced; 3/4 plate movements of high quality with Illinois superior motor barrel, double roller and patent regulator.

Observations,
The movements mostly come in a broad striped pattern named The Marquis, Marquis Autocrat and Private label Spaulding & Co. The Aluninum
movements have a bright striped pattern. Early models have burnished set jewels, this later changed to screw set jewels. Also a pallet cock was fitted
to early models this changed to a pallet bridge. Silver snap on bezel dials of various designs were fitted and a variety of gold and gold filled named
cases were advertised, Acorn; Oxford; Cambridge; Eton; Pioneer; Barrister; Trustee; and Dean made by Keystone; Fahys; Wadsworth and Solidarity.
The watches were factory cased.

Description,
17 ruby and sapphire jewels of extra quality; adjusted to 3 positions, temperature and isochronism; beveled arm gold center wheel; Breguet
hairspring; patent regulator; concave and polished winding wheels; recoil safety click; hardened spring tempered compensating balance; and Illinois
motor barrel.
Images, 1 Illinois Watch Co. Aluminum model. 2 The Marqius model. 3 Spaulding & Co. 4 The Marquis Autocrat model.