SiO2系列常见宝石品种包括水晶、石英岩、玉髓、欧泊和熔炼石英玻璃。通过对 各个品种宝石的镜面反射红外光谱和直接透射红外光谱进行对比，得出随着宝石结晶程度的变化，Si-O键的伸缩 振动谱带及合频谱带具有一定的递变规律，而且在巨晶水晶的红外光谱中，Si-O键表现出了明确的方向 性。此外，OH键在该类宝石中具有重要作用，其伸缩振动谱带(3600cm-1 ～ 3200cm-1)也与 宝石的结晶程度呈现出递变规律。与Si-O键相关的谱带递变规律对于确定相关宝石的晶体形态进而准 确定名具有重要意义，而Si-O键的方向性也为区分天然与合成水晶提供了重要的帮助。

The common SiO2 gem include crystal,quartzite,chalcedony,opal and glass. Through careful contrast of the mirror reflective infrared spectra and transmission infrared spectra of these gemstone, it is found that with the change of the gemstone in crystallinity, the flex vibration spectral band etc. of the Si-O have a certain progressive change regularity. Moreover, the Si-O exhibit its orientation in the infrared spectra of large crystals. In addition, the O-H plays an important role in these gemstones. Its flex vibration in the range of 3600 cm-1 to 3200 cm-1 is related to their crystallinity. The regularity is of importance to the determination of the crystallinity of some new gemstones composed of SiO2 and the orientation of Si-O is also helpful to the distinguishing of the natural rock crystals from the synthetic ones.