Here's a list of all elements on the periodic table that have an atomic mass between 50-100 (I've included atomic mass, name, symbol, and atomic number.
98 Technetium Tc 43 95.94 Molybdenum Mo 42 92.9064 Niobium Nb 41 91.224 Zirconium Zr 40 88.9059 Yttrium Y 39 87.62 Strontium Sr 38 85.4678 Rubidium Rb 37 83.8 Krypton Kr 36 79.904 Bromine Br 35 78.96 Selenium Se 34 74.9216 Arsenic As 33 72.64 Germanium Ge 32 69.723 Gallium Ga 31 65.39 Zinc Zn 30 63.546 Copper Cu 29 58.9332 Cobalt Co 27 58.6934 Nickel Ni 28 55.845 Iron Fe 26 54.938 Manganese Mn 25 51.9961 Chromium Cr 24 50.9415 Vanadium V 23
Now just cross-reference them against this list of all metals on the periodic table and you should be able to whittle it down to the ones that are metals only.
Elementary!