Recent work in our laboratory has shown that metal-stacking reactions of Cp*Co(Et(2)C(2)B(3)H(3)X)(-) anions (X = alkyl, acyl, halogen) with metal halides generate air-stable tetradecker sandwiches of the type [Cp*Co(Et(2)C(2)B(3)H(2)X)](2)M in which M is Co, CoH, Ni, Ru, Rh, or Ir. However, attempts to prepare analogous Co-Fe-Co tetradeckers via reactions with FeCl2 have given only Co2C4B6 fused clusters or uncharacterizable products. It has been assumed that Fe-centered tetradeckers are formed in such reactions but undergo oxidative fusion during the usual workup on silica in air. We have confirmed this hypothesis via the synthesis and isolation of iron-centered [Cp*Co(Et(2)C(2)B(3)H(2)X)]2FeH sandwiches (1, X = Cl; 2, X = Me) while avoiding contact with silica in air and demonstrating that both species undergo air oxidation to form respectively the fused products Cp*Co-2(2)(Et(4)C(4)B(6)H(4)X(2)) (5, X = Cl; 6, X = Me). Different cage structures are exhibited by 5, a previously prepared and structurally characterized compound, and 6, whose geometry was established in this work by X-ray crystallography. The structural relationships between these cages and those of other known Co2C4B6 clusters are examined from mechanistic and skeletal electron-counting viewpoints. Crystal data for 6 : space group P2(1)/c; a = 15.737(5) Angstrom, b = 13.575(4) Angstrom, c = 17.212(5) Angstrom, beta = 111.13(2)degrees; Z = 4; R = 0.058 for 3340 independent reflections having I > 3 sigma(I).