So, how can someone tell when a Rolex watch was manufactured...well, for pre 8/10 watches, you can use the following info to discover the year:
Locating your Rolex serial and model number
The serial number of your watch is engraved on the case at the 6 o'clock end between the lugs. You will need to remove the bracelet/strap to see it. The model reference is engraved in the same place at the 12 o'clock end. As of August 2010, serial numbers for new Rolex watches are randomized, making it impossible to use the numbers for dating purposes.
Rolex serial numbers 1921-1930
25000+ (1925)
28000+ (1926)
30000+ (1927)
33000+ (1928)
35000+ (1929)
38000+ (1930)
Rolex serial numbers 1931-1940
40000+ (1931)
42000+ (1932)
45000+ (1933)
49000+ (1934)
63000+ (1935)
81000+ (1936)
99000+ (1937)
117000+ (1938)
135000+ (1939)
164000+ (1940)
Rolex serial numbers 1941-1950
194000+ (1941)
223000+ (1942)
253000+ (1943)
283000+ (1944)
348000+ (1945)
413000+ (1946)
490000+ (1947)
550000+ (1948)
608000+ (1949)
673000+ (1950)
Rolex serial numbers 1951-1960
737000+ (1951)
804000+ (1952)
869000+ (1953)
934000+ (1954)
1105000+ (1955)
1090000+ (1956)
1170000+ (1957)
1240000+ (1958)
1320000+ (1959)
1400000+ (1960)
Rolex serial numbers 1961-1970
1480000+ (1961)
1558000+ (1962)
1663000+ (1963)
1710000+ (1964)
1792000+ (1965)
1870000+ (1966)
2160000+ (1967)
2420000+ (1968)
2680000+ (1969)
2950000+ (1970)
Rolex serial numbers 1971-1980
3210000+ (1971)
3470000+ (1972)
3740000+ (1973)
4000000+ (1974)
4280000+ (1975)
4530000+ (1976)
5000000+ (1977)
5400000+ (1978)
5900000+ (1979)
6400000+ (1980)
Rolex serial numbers 1981-1990
6900000+ (1981)
7300000+ (1982)
7800000+ (1983)
8300000+ (1984)
8600000+ (1985)
9290000+ (1986)
9760000+ (1987)
R000000+ (1987)
L000000+ (1989)
E000000+ (1990)
Rolex serial numbers 1991-2000
X000000+ (1991)
N000000+ (1991)
C000000+ (1992)
S000000+ (1993)
W000000+ (1995)
T000000+ (1996)
U000000+ (1997)
A000000+ (1998)
P000000+ (2000)
Rolex serial numbers 2001-2010
K000000+ (2001)
Y000000+ (2002)
F000000+ (2004)
D000000+ (2005)
Z000000+ (2006)
M000000+ (2008)
V000000+ (2009)
G000000+ (2010)
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