The invention relates to a tempered glass comprising, in terms of mass percent, SiO2: 60 to 80%; Al2O3: 3 to 18%; B2O3: 0 to 7%; Li2O: 0.01 to 10%; Na2O: 4 to 16%; K2O: 0 to 15%; and R′O (wherein R′O indicates a total content of alkaline earth metal oxides): 0 to 5%, wherein a value of (Li2O+Al2O3)/(Na2O+K2O) in terms of molar ratio is within a range of 0.1 to 2, and wherein a surface of the tempered glass is treated to form a compressive stress layer.
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