What this coin looks like (obverse, reverse, mint mark location, special features, etc.): All 1922 Lincoln Wheat Cents (Pennies) were minted at the Denver Mint and should have received a "D" mintmark. An issue arised at the Denver Mint where the coin dies used to strike coins were being overworked and overused. Some coins would receive a weak "D" mint mark and in some very rare cases the mint mark would be completely missing. The rest of the coin features would have a weaker strike as well since the dies were so worn out. The "No D" variety is the rarest and most valuable. One way to tell the difference between the "Weak D" and the "No D" is the fact that the "No D" variety has no trace of the mint mark. In addition: The last "2" is typically clearer than the rest of the date and the word "TRUST" is much clearer than the rest of the words in the motto "IN GOD WE TRUST" on the obverse of the coin as depicted in the example image above. Some coins will have a "Strong Reverse" or a "Strong Obverse" which means that the worn out dies were just replaced with new ones. Example image is courtesy of Heritage Auctions.
Coin value chart: Typical coin prices, values and worth in USD based on grade/condition