The value of a 1921 one cent piece with "Georgius V D G Britt Omn Rex F D Ind" depends on its condition and rarity. Generally speaking, coins in good condition can be worth anywhere from a few dollars to a few hundred dollars. However, some rare varieties can sell for significantly higher prices. For example, a 1921 penny with the "Broken 8" variety, where the lower loop of the "8" is broken, can be worth several thousand dollars.
To determine the exact value of your 1921 one cent piece, it is recommended that you consult with a professional numismatist or coin dealer who can assess its condition and rarity accurately.