You don't. Cleaning coins destroys any value they have and takes what could be a coin worth a few cents back down to face value. Never, ever, ever clean coins unless you want to completely destroy their value.
Superstition Mountains was created in 1939.
Minions of the Moon was created in 1939.
The Bismarck battleship was launched on February 14, 1939 in Hamburg, Germany.
By 1939, the only space travel that had been achieved was through unmanned scientific rockets that reached the edge of space. The first liquid-fueled rocket to reach the Earth's upper atmosphere was launched in 1935 by Robert Goddard in the United States. However, there were no manned spaceflights or orbital missions conducted by 1939.
Franklin D. Roosevelt was the first president to appear on television in 1939 at the opening ceremonies of the New York World's Fair.
They all look the same except for different dates and mintmarks. Lincoln on the obverse and Wheat Ears on the reverse.
You can retrieve this information by going to the following link: http://coins.ha.com/info/typevalues.php
The value depends on the grade of the coin, the 1939-S Lincoln is not rare, retail values are from 25 cents to $1.50 for circulated coins.
0.15-0.50 $
1939 is not a rare date for Lincoln cents. Values for a Denver-mint coin range from a quarter for a worn one up to about a dollar for one in nearly-new condition.
1939 is a common date wheat penny, most coins in average condition are valued at 3 to 10 cents.
The 1939 Lincoln cent is a very common coin. Most circulated coins have values of 5 to 10 cents.
1939 Lincoln with no mint mark, average value is 5 to 10 cents.
1939 Lincoln, Wheat Ears Reverse (Wheat Penny): With no mint mark, in very good condition is worth $0.05, uncirculated is worth $3.00, proof is worth $35.00. With D mint mark, in very good condition is worth $0.45, uncirculated is worth $11.00. With S mint mark, in very good condition is worth $0.15, uncirculated is worth $8.00.
It's a common date, currently worth around 10 cents.
The 1939 Lincoln cent is a very common coin. Most circulated coins have values of 5 to 10 cents.
About 5 cents if in circulated condition or a couple of bucks if uncirculated. It isn't a rare date.