In fact the original designs were intended for a half dollar. Although Treasury Secretary Andrew Mellon agreed on the Commission of Fine Arts recommendation for a commemorative half, Congress over ruled replacing the Standing Liberty quarter
I'm afraid that this statement does not align with the facts.
The George Washington Bicentennial Commission did originally conceive of a special half dollar that it could sell for a premium as a special memorial coin. The Treasury Department, however, had been voicing its opposition to such souvenir commemorative coins for years and continued to do so regarding the Bicentennial Commission's original and informal proposal; the Treasury received a letter from the Commission in April 1930. After consulting with the Treasury, the Commission moved away from its half dollar thoughts and got on board with the Treasury's 25-cent coin plan.
It was, in fact, Secretary Mellon who sent a letter to Congress expressing, on behalf of the Treasury Department, the preference for replacing the Standing Liberty design on the quarter with one commemorating George Washington; the letter had attached to it draft language for a coinage bill to that effect. (The Treasury was in favor to replacing the Standing Liberty design due to the difficulties it had in properly striking Hermon MacNeil's detailed design.)
A Hearing for the proposed coin was held on February 13, 1931 by the House Committee on Coinage, Weights, and Measures at which the Treasury Department again voiced its objection to special souvenir coins and its preference for replacing the design of the Standing Liberty quarter
vs. striking a special commemorative 50-cent piece. The Committee's subsequent report stated its support for the striking of a George Washington quarter
No bill calling for a George Washington Bicentennial 50-cent coin was introduced in either the Senate or House, only bills for proposed 25-cent coins were offered for consideration. In each of the bills offered, Congress respected the wishes of the Treasury Department for a 25-cent coin - it did not
overrule it. Also, the coin's design contest was held knowing that the new Washington Bicentennial coin would be a quarter-dollar coin and not a half-dollar coin - the designs were never intended for a half dollar.
Collecting history one coin or medal at a time! (c) commems. All rights reserved.