The ballen silica shows fairly weak (faint) CL with homogeneous feature in its grain exhibiting almost same spectral pattern with two broad band peaks at around 390 and 650 nm, which might be assigned to self-trapped excitons (STE) or an intrinsic and nonbridging oxygen hole centers (NBOHC), respectively, recognized in amorphous and crystalline silica. In addition, ballen silica from Lappajärvi crater shows bright and heterogeneous CL with a broad band centered at around 410 nm, presumably attributed to [AlO4/M+]0 centers or self-trapped excitons (STE). Micro-Raman and micro-XRD analyses show that fairly homogeneous CL part is alpha-quartz and heterogeneous CL part is composed of alpha-cristobalite and alpha-quartz. These indicate that ballen silica could be formed in the quenching process from relatively high temperature.
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机译：球形二氧化硅显示出相当弱的（微弱的）CL，其晶粒具有均一的特征，显示出几乎相同的光谱模式，并在390和650 nm附近出现两个宽带峰，这可能归因于自陷激子（STE）或固有的和非桥接的氧孔中心（NBOHC）分别在无定形和结晶二氧化硅中识别。此外，来自拉帕哈维火山口的球形二氧化硅显示出明亮且不均一的CL，其宽带集中在410 nm左右，可能归因于[AlO4 / M +] 0中心或自陷激子（STE）。微观拉曼和微观XRD分析表明，相当均匀的CL部分是α-石英，而异质的CL部分由α-方石英和α-石英组成。这些表明，在相对高的温度下，在淬灭过程中可能形成氧化硅。
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