中文摘要：

采用X射线粉末衍射（XRD）、扫描电子显微镜（SEM）、热重分析（TG-DTG）及激光诱导离解光谱（LIBS）等分析方法对一种红色砭石的矿物学特征进行了深入的研究。XRD分析表明，红色砭石主要由白云石组成，并含有少量石英和方解石及微量云母、正长石和赤铁矿。SEM结果显示，砭石中的矿物颗粒大多为集合体，粒径大多集中在1～5μm之间，表面光滑程度有所不同。红色砭石在650-850℃范围内出现一个单失重峰，为白云石的分解形成，类质同象或者杂质矿物的存在导致白云石两阶段的分解同步完成。红色砭石的颜色可能与赤铁矿和正长石微晶在砭石中的均匀分布有关。

英文摘要：

This paper investigates the mineralogical characteristics of a kind of red stone needle by using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, thermogravimetric analysis （TG-DTG） and laser induced breakdown spectroscopy （LIBS）. The XRD result shows that the red stone needle is mainly composed of dolomite, containing minor quartz and calcite, and trace mica, orthoclase and hematite. SEM result indicates that mineral aggregates dominate in the red stone needle with their grain size ranging from 1μm to 5 μm and different degrees of smoothness on their surfaces. A single weightlessness peak occurs between 650 ℃ and 850℃, which should be attributed to the thermal decomposition of dolomite and the occurrence of isomorphism or foreign minerals leading to the simultaneous accomplishment of the two-stage decompositions. The coloration might result from the average distribution of hematite and orthoclase in the red stone needle.