A nickel-base casting superalloy consisting (by weight of the alloy) of 7% to 25% chromium, 0.2% to 7% aluminum, 0.2% to 6% titanium, 0.01% to 0.25% carbon, up to 0.2% zirconium, up to 0.15% boron, up to 3% hafnium, at least 5% of a matrix-strengthening element selected from the group consisting of 0 to 25% cobalt, 0 to 10% molybdenum, 0 to 13% tungsten, 0 to 6% tantalum, 0 to 5% columbium, and 0 to 1.5% vanadium, a carbide shape controller selected from 0.022% to 0.15% magnesium, 0.005% to 0.1% calcium, or mixtures thereof, and the balance nickel except for impurities said alloy in the as-cast condition having a fine grain macrostructure in thick as well as thin sections, exhibiting a microstructure having precipitated carbide particles which are substantially equi-axed in shape and well-distributed through the alloy with a substantial portion of the carbide shape controller content of the alloy concentrated in such particles and at grain boundaries, and displaying in its thick sections a tensile strength and elongation substantially higher than a corresponding thick-section alloy having a microstructure exhibiting script-like carbide particles substantially free internally and at grain boundaries of said carbide shape controller. Silver base casting alloys for dental use which have a yellow color. They are useful for the manufacture of crowns, bridges and other dental prosthesis and such dental prosthesis are within the scope of the invention. The dental alloys consist essentially of 40-60% silver, 15-20% indium, 8-15% copper, 0.1-2% nickel, 0.1-2% zinc, from 0-10% gold and/or from 0-30% palladium. The total of gold and palladium content is between 10 and 30%.