石英晶簇与萤石八面体晶体（fluotite）
产地：湖南临武
特征：
石英的化学成分为SiO2，晶体属三方晶系的氧化物矿物，即低温石英（a-石英），是石英族矿物中分布最广的一个矿物种。广义的石英还包括高温石英（b-石英）。低温石英常呈带尖顶的六方柱状晶体产出，柱面有横纹，类似于六方双锥状的尖顶实际上是由两个菱面体单形所形成的。石英集合体通常呈粒状、块状或晶簇、晶腺等。纯净的石英无色透明，玻璃光泽，贝壳状断口上具油脂光泽，无解理。受压或受热能产生电效应。
萤石（Fluorite），又称氟石，氟石粉，萤石粉；是一种矿物，等轴晶系，其主要成分是氟化钙（CaF2），含杂质较多，Ca常被Y和Ce等稀土元素替代，此外还含有少量的Fe2O3，SiO2和微量的Cl，O3，He等。自然界中的萤石常显鲜艳的颜色，部分可发出荧光，莫氏硬度4，低于钢，易划伤，质脆，甘、涩、无毒；熔点：1270-1350℃。密度：3.18g/cm³，折射率：1.434；它可以用于制备氟化氢：CaF2 + H2SO4 = CaSO4 + 2HF↑；是制造镜头所用光学玻璃的材料之一。世界萤石产量的一半用以制造氢氟酸，进而发展制造冰晶石，用于炼铝工业等。电冰箱里的冷却剂（氟利昂）要用萤石；1986年，中国第一代人造血液也要用萤石。
Drusy quartz and octahedral fluorite
Provenance: Linwu, Hunan, China
Characteristics:
Quartz is the second-most-abundant mineral in Earth's continental crust, after feldspar. Its crystal structure is a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2.There are many different varieties of quartz, several of which are semi-precious gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Europe and the Middle East.
Fluoride is an inorganic, monatomic anion of fluorine with the chemical formula F−.Fluoride is the simplest anion of fluorine. Its salts and minerals are important chemical reagents and industrial chemicals, mainly used in the production of hydrogen fluoride for fluorocarbons. In terms of charge and size, the fluoride ion resembles the hydroxide ion. Fluoride ions occur on earth in several minerals, particularly fluorite, but are only present in trace quantities in water. Fluoride contributes a distinctive bitter taste. It contributes no color to fluoride salts.