[MichaelGroves]

Probably 664 is what they had available, or what their calculated geometry called for. It seems silly to speculate that they could have or should have gone for 666 but deliberately chose not to. If that were the case, why not 665 or 667? Is there any reason to think 666 would have been a more appropriate number?

[qubex]

Having seen photographs of the “diabolical chandelier” I expected 664 to be a centred cubic number, but it isn’t. That leaves me somewhat perplexed as to how they actually arranged the geometry of the fissile material.