I-spinel yiminerali eyenziwe nge-magnesium kunye ne-aluminium oxide, kuba iqulethe i-magnesium, isinyithi, i-zinc, i-manganese kunye nezinye izinto, zinokwahlulwa zibe ziindidi ezininzi, ezifana ne-aluminium spinel, i-iron spinel, i-zinc spinel, i-manganese spinel, i-chrome spinel kunye njalo njalo.