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The search for alternative nuclear fuels, materials suitable for nuclear waste repositories, and new superconducting materials has been underway for decades. We have explored metal flux and mixed-metal flux synthesis and supercritical hydrothermal synthesis to grow bulk crystals of compounds with potential for such applications. Metal and mixed-metal flux synthesis uses an excess of a low-melting metal or metal mixture as a solvent for crystal growth. Reactants are able to dissolve in the flux and create chemical bonds with one another as well as with the flux itself. A new arc melter has been built to premelt some of the starting materials. In this work, six new compounds have been grown from metal fluxes: two borides with Al substitution on the V sites (UV0.43Al0.57B4), and four structurally related stuffed superstructures: U8Al19Si6 (cubic), U8Al19Si6 (tetragonal), Np8Al19Si6 (tetragonal), and Pu8Al19Si6 (tetragonal). Supercritical hydrothermal reactions were carried out in a high pressure/high temperature superalloy autoclave. The supercritical water provides counterpressure on the thermally expanding sealed reaction ampules within. UO2 crystals approaching 2 mm in diameter have been grown from the supercritical reactions. These crystals have been sent to universities and national laboratories for further chemical and physical analyses.