This figure shows the (a) U.S. and (b) Russian versions of the Pu-Ga phase diagram. The Russian version, with a eutectoid point of 97°C and 7.9 at.% Ga, is considered to be the equilibrium phase diagram. If the diagram is correct, the d-phase should decompose below 97°C into a-phase+Pu3Ga. The U.S. version, in which the d-phase is retained at least down to room temperature, is considered to be an adequate working diagram. These images appear as Figure 3 in the article by Siegfried S. Hecker, “Plutonium: Coping with Instability,” in the September 2003 JOM, pp. 13–18, 50.