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The magnetic circular dichroism (MCD) of $IrCl62-$ doped into $(CH\ast \ast \ast NH3)2SnCl6$ has been studied as a function of temperature from liquid helium to room temperature over the region 7000-3000 {\AA}. The results confirm the new assignment (based on solution MCD data) of the first two allowed charge-transfer bands so that the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}T1u$ state lies at lower energy than $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}T2a$. The spin-orbit splitting of the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}T2u$ state which is not apparent in the absorption spectrum or solution MCD shows up strikingly in the crystal MCD illustrating the potentialities of crystal MCD studies, particularly at low temperatures. The MCD data show the expeted 1/T temperature dependence.