The electromagnetic mass splittings of heavier hadrons are estimated in the framework of gauge theory model where ligher quarks are taken to behave relativistically and the spatial wave functions are described by the spin-spin interaction affected relative distances between quarks. The predictions for (Ξ−-Ξ0), (Σ*0−Σ*+), (Ξ*−-Ξ*0), (Dc+−Dc0) and (Dc*+−Dc*0) are in fair agreement with the experimental data available whereas those for (Db−−Db0) and (Db*−−Db*0) are in qualitative agreement with other theoretical estimates.
