It was difficult to arrive at a proper price, General Groves explains (in Now It Can Be Told: The Story of the Manhattan Project), for uranium ore:
By this time it was certain that the material was of immense value to the United States, provided the bomb worked. To the seller it was of great potential value if atomic energy should prove to have either military or peacetime value. Otherwise, it was worth only the value of its radium content. And if our reactor theories were sound, the radium would lose most of its value since radioactive cobalt could largely replace it.
It did have one definite value and that was what it cost to produce. Yet even this was difficult to establish fairly, for the unit production cost was much less at Shinkolobwe than in Canada or on the Colorado Plateau. Its value had never been determined in the open market and now there was only one purchaser and one seller.
As a Belgian, Sengier appreciated fully the absolute necessity of an Allied victory. It was his broad, statesman-like attitude that made it possible for us to reach an agreement satisfactory to all.
It was a distinct pleasure for me after the war to recommend the award of the Medal of Merit, the highest civilian award made by our government, to Edgar Sengier for his great services to the United States, to Belgium and the free world in making available to us adequate supplies of Belgian Congo uranium. It was also my pleasure to present this award at a ceremony in my office in Washington. Security restrictions had not yet been lifted on this phase of the MED operations and the ceremony was private and unpublicized. It has always been a source of regret to me that Sengier’s services, and particularly his foresight, could not receive full public recognition at the time.