The San Francisco Mint struck Lincoln cents in 1970 that carry two distinct date styles.
One of those styles is known as the Small Date variety.
Collectors pay close attention to this coin because it is much harder to find than the standard Large Date version.
The "RD" label stands for Red, meaning the copper penny still has its bright, original mint color.
Most copper cents turn brown or red-brown over time as they react to air and handling.
Finding a 1970-S Small Date that kept its original red surface is tough for collectors.
This variety ranks at number 23 on our list of the 200 most valuable pennies.
It remains one of the most famous modern Lincoln cent varieties ever discovered.
A top-quality example of this coin brought a winning bid of $10,063.
Heritage Auctions handled the sale of this piece in January 2008.
Professional coin graders certified the coin at a grade of MS-66 Red.
MS stands for Mint State, which means the coin never circulated in pocket change.
On the 70-point grading scale, a 66 is a very high grade for a modern copper coin.
It means the penny has a clean strike, excellent eye appeal, and very few tiny contact marks.
Most coins pulled from pocket change or old jars will not grade anywhere near this level.
High auction records like this come from certified, high-grade coins that collectors fight over in competitive bidding.
Condition rarity is the biggest factor behind the five-figure price tag.
The Mint struck far fewer Small Date dies than Large Date dies for the 1970-S cent.
Because of this, the Small Date variety is much scarcer across every grade.
It is especially tough to find in high Mint State grades with full red luster.
Copper is a delicate metal that spots and tarnishes easily over the decades.
Many surviving 1970-S pennies developed dark spots or faded to brown while stored in proof sets or rolls.
Collectors who build top registry sets need the best possible examples to complete their collections.
When an MS-66 Red Small Date crosses the auction block, serious specialists are willing to bid top dollar.
To inspect your coin, you will need good lighting and a magnifying glass or jeweler's loupe.
First, look below the date on the front of the coin for the "S" mint mark.
If you see the "S", zoom in closely on the four digits of the date "1970".
Look specifically at the top of the digit "7" compared to the other numbers.
On the Small Date variety, the top bar of the 7 sits visibly lower than the tops of the "1", "9", and "0".
On the common Large Date variety, all four digits are level across the top.
You can also use an app like Coin Value Checker to snap a photo and get a quick first pass on your coin.
Remember that the coin must also have its original, bright copper luster to earn the "RD" designation.
If your coin is dark brown or shows heavy wear, it will not carry the massive value of an uncirculated gem.
Checking the alignment of the 7 is the fastest way to know what you have in your hand.
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