a protective cover that protects the face of a watch | a mental synthesis that becomes fixed or concrete by a process resembling crystal formation |
glassware made of quartz | a rock formed by the solidification of a substance; has regularly repeating internal structure; external plane faces |
a crystalline element used as a component in various electronic devices | the formation of crystals |
a rock formed by the solidification of a substance; has regularly repeating internal structure; external plane faces | |
a solid formed by the solidification of a chemical and having a highly regular atomic structure | |
colorless glass made of almost pure silica | |