You can provide the most accurate answer to this valid question.
In his book The Guyana Story, Odeen Ishmael writes: "The  general election, held under the "first past the post" system, took place on 27 April 1953. The total number of voters registered in a house to house enumeration was 208,939. Almost 150,000 were newly qualified because of the extended franchise resulting from the granting of universal adult suffrage. Of this number, an estimated 40,000 were illiterate, and special arrangements had to be made to enable them to vote. These included the introduction of symbols for political parties and independent candidates, and separate ballot boxes for each candidate. Each ballot box was marked with the name and photograph and symbol of the candidate. The symbols were chosen long before nomination day, and all voters knew whom they represented. The PPP, as a political party, adopted the cup as its symbol and all its candidates used it during their campaign to educate voters, particularly the illiterate, on how to mark their ballots."
@Shaitaan, I have an enamel cup in front of me right now. It's marked THE OFFICIAL MOUNT GAY RUM RATION. I had got it attached to a bottle Barbados rum as a Xmas gift.