ruby is a hard stone just like diamond which is a result of its crystalline nature and can be used to cut glass.
红宝石是一种就象鉆石般坚硬的石头,那是它晶态性质的结果,可以用来切割玻璃。
the difference in the crystalline nature of the films grown on the glass substrate and gold-coated glass substrate is most likely due to the energetic species bombardment.