磁铁矿

FeO31.03%，Fe2O368.97%或含Fe72.2%，O27.6%，等轴晶系。单晶体常呈八面体，较少呈菱形十二面体。在菱形十二面体面上，长对角线方向常现条纹。集合体多呈致密块状和粒状。颜色为铁黑色、条痕为黑色，半金属光泽，不透明。硬度5.5～6.5。

赤铁矿

Fe69.94%，O30.06%，常含类质同象混入物Ti、Al、Mn、Fe2 、Ca、Mg及少量Ga和Co。三方晶系，完好晶体少见。结晶赤铁矿为钢灰色，隐晶质；土状赤铁矿呈红色。条痕为樱桃红色或鲜猪肝色。金属至半金属光泽。有时光泽暗淡。硬度5～6。比重5～5.3。

磁赤铁矿

γ-Fe2O3，其化学组成中常含有Mg、Ti和Mn等混入物。等轴晶系，五角三四面体晶类，多呈粒状集合体，致密块状，常具磁铁矿假象。颜色及条痕均为褐色，硬度5，比重4.88，强磁性。

Symbiotic minerals.

菱铁矿

siderite

磁铁矿

magnetite

FeO31.03%，Fe2O368.97%或含Fe72.2%，O27.6%，等轴晶系。单晶体常呈八面体，较少呈菱形十二面体。在菱形十二面体面上，长对角线方向常现条纹。集合体多呈致密块状和粒状。颜色为铁黑色、条痕为黑色，半金属光泽，不透明。硬度5.5～6.5。

FeO31.03%, Fe2O368.97% or Fe72.2%, O27.6%, etc.. The single crystal body is usually in a eight surface body, which is less than twelve in a diamond. In the diamond twelve face, the long diagonal line is often striped. The aggregate is dense and massive and granular. The color is black, iron streak of black, semi metallic luster, opaque. Hardness 5.5 ~ 6.5.

赤铁矿

hematite

Fe69.94%，O30.06%，常含类质同象混入物Ti、Al、Mn、Fe2 、Ca、Mg及少量Ga和Co。三方晶系，完好晶体少见。结晶赤铁矿为钢灰色，隐晶质；土状赤铁矿呈红色。条痕为樱桃红色或鲜猪肝色。金属至半金属光泽。有时光泽暗淡。硬度5～6。比重5～5.3。

Fe69.94%, O30.06%,, Mn, Fe2, Ca,, Mg, Ga, Co,, Al and Ti. Three party system, good crystal rare. Crystalline hematite is steel grey, aphanitic earthy hematite is red. Streak of cherry red or bright red. Metal to semi metallic luster. Sometimes dull. Hardness 5 ~ 6. Specific gravity of 5 to 5.3.

磁赤铁矿

maghemite

γ-Fe2O3，其化学组成中常含有Mg、Ti和Mn等混入物。等轴晶系，五角三四面体晶类，多呈粒状集合体，致密块状，常具磁铁矿假象。颜色及条痕均为褐色，硬度5，比重4.88，强磁性。

-Fe2O3, its chemical composition often contains Ti, Mn and Mg, etc.. Such as the axis of the system, the five angle of three tetrahedral crystal class, more granular aggregates, compact block, often with magnetite. Color and streak are brown, hardness of 5, the proportion of 4.88, with strong magnetism.