自然铜、 蛇含石、 代赭石与磁石均为含铁矿物药, 市场上多见伪品或混用现象, 这与矿物学鉴定不准确有直接关系。 通过性状观察及反光镜鉴定, 利用扫描电子显微镜、 X射线衍射、 微量元素光谱半定量、 红外光谱等测试对4种含铁矿物药进行矿物学及谱学鉴定。 结果如下: (1)性状鉴定显示矿物药自然铜、 蛇含石矿物学均归属为黄铁矿, 代赭石为赤铁矿混有少量褐铁矿, 磁石为磁铁矿。 (2)反光镜测得自然铜反射率约53%, 蛇含石反射率约50%, 代赭石反射率约47%, 磁石反射率约20%, 均无内反射, 为均质体。 (3)扫描电镜观察发现, 自然铜为立方体, 蛇含石为结核状集合体, 代赭石为粒状, 磁石为块状。 (4)X射线衍射结果显示, 自然铜样品中主要衍射线为2.704(10), 1.631(9)和2.513(8), 黄铁矿含量约95%, 褐铁矿5%。 蛇含石样品中主要衍射线为2.705(10)和1.631(10), 黄铁矿含量约99%。 代赭石样品中主要衍射线为2.702(10)和2.519(9), 赤铁矿含量约95%, 另可见3.351(10), 4.250(8)和1.800(8), 石英含量约5%。 磁石样品中主要衍射线为7.030(10), 2.957(9), 2.525(8), 2.094(7)和1.460(6), 磁铁矿含量约98%。 (5)微量元素光谱半定量分析显示4种矿物药中均含有Cu, Mo, Co和Mn, 微量元素种类与含量差异在于自然铜中含有Yb和B, 蛇含石中含有Pb, Sn, Ni和Yb, 代赭石中含有Zn, Pb, Ga, V, Ge和In, 磁石中含有Zn, Pb, Ni, Be和Sr。 (6)红外光谱曲线显示自然铜特征谱线417和343 cm^-1; 蛇含石特征谱线413和345 cm^-1; 磁石中特征谱线569 cm^-1; 代赭石特征谱线1 083, 531, 452和320 cm^-1, 石英含量5%, 特征谱线1 083, 799, 698和398 cm^-1, 软锰矿少量。 综上, 单纯使用性状鉴定不易有效区别4种含铁矿物药, 而辅以红外光谱、 X射线衍射测试则能有效鉴别。

Pyrite, limonite, red ochre, and magnet are iron-containing mineral medicines. There are many fake or mixed-use phenomena in the market. This is directly related to the inaccuracy of mineralogical identification. This article aims to conduct mineralogical and spectroscopic identification of four iron-containing mineral medicines through character observation and mirror identification using scanning electron microscopy(SEM), X-ray diffraction(XRD), and semi-quantitative trace elements spectroscopy, and infrared spectroscopy(IR). The results are as follows: (1) The character identification shows that pyrite and limonite belong to pyrite, the red ochre is hematite mixed with a small amount of limonite, and the magnet is magnetite. (2) The reflectance of pyrite measured by the reflector is about 53%, the reflectance of limonite is about 50%, the reflectance of red ochre is about 47%, and the reflectance of the magnet is about 20%. There is no internal reflection, and it is a homogeneous body. (3) SEM observation revealed that the pyrite is cubic, the limonite is a nodular aggregate, the red ochre is granular, and the magnet is massive. (4) XRD results show that the main diffraction lines in pyrite are 2.704 (10), 1.631 (9), 1.912 (8), 2.704 (10), 2.513 (8). The content of pyrite and limonite is about 95%, 5%. The main diffraction lines in limonite are 2.705 (10), 1.631 (10), and the content of pyrite is about 99%. The main diffraction lines in the red ochre sample are 2.702 (10), 2.519 (9), and the content of hematite is about 95%,and 3.351 (10), 4.250 (8), 1.800 (8), quartz is about 97%. The main diffraction lines in the magnet sample are 7.030(10), 2.957(9), 2.525(8), 2.094(7), 1.460(6). the content of the magnet is about 98%. (5) Semi-quantitative analysis of trace element spectroscopy shows that the types of trace elements are Cu, Mo, Co, and Mn, but pyrite contains Yb, B, limonite contains Pb, Sn, Ni, Yb, red ochre contains Zn, Pb, Ga, V, Ge, In, and magnet contains Zn, Pb, Ni , Be, Sr. (6) The IR shows that the characteristic spectrum lines of pyrite are 417, 343 cm^-1; the limonite is 413, 345 cm^-1; the red ochre is 569 cm^-1, and the magnet is 1 083, 531, 452, 320 cm^-1. It is not easy to effectively distinguish the four iron-containing mineral medicines by simply using the character identification, while supplemented by infrared spectroscopy and X-ray diffraction tests can effectively identify them.