Glass compositions with improved chemical and mechanical durability

A glass composition comprising:

• from about 74 mol. % to about 78 mol. % SiO2;
• from about 4 mol. % to about 8 mol. % alkaline earth oxide, wherein the alkaline earth oxide comprises both MgO and CaO, CaO is present in an amount greater than or equal to about 0.1 mol. % and less than or equal to about 1.0 mol. %, and a ratio (CaO (mol. %)/(CaO (mol. %)+MgO (mol. %))) is less than or equal to 0.5;
• X mol. % Al2O3, wherein X is greater than or equal to about 2 mol. % and less than or equal to about 10 mol. %;
• and
• Y mol. % alkali oxide, wherein the alkali oxide comprises Na2O in an amount greater than or equal to about 9 mol. % and less than or equal to about 15 mol. %, a ratio of Y:X is greater than 1, and the glass composition is free of boron and compounds of boron.

A glass composition comprising:

• from about 74 mol. % to about 78 mol. % SiO2;
• alkaline earth oxide comprising both CaO and MgO, wherein the alkaline earth oxide comprises CaO in an amount greater than or equal to about 0.1 mol. % and less than or equal to about 1.0 mol. %, and a ratio (CaO (mol. %)/(CaO (mol. %)+MgO (mol. %))) is less than or equal to 0.5;
• X mol. % Al2O3, wherein X is greater than or equal to about 2 mol. % and less than or equal to about 10 mol. %;
• and
• Y mol. % alkali oxide, wherein the alkali oxide comprises from about 0.01 mol. % to about 1.0 mol. % K2O and a ratio of Y:X is greater than 1, and the glass composition is free of boron and compounds of boron.

A glass composition comprising:

• from about 74 mol. % to about 78 mol. % SiO2;
• from about 4 mol. % to about 8 mol. % alkaline earth oxide, wherein the alkaline earth oxide comprises CaO in an amount greater than or equal to about 0.1 mol. % and less than or equal to about 1.0 mol. %, MgO, and a ratio (CaO (mol. %)/(CaO (mol. %)+MgO (mol. %))) is less than or equal to 0.5;
• X mol. % Al2O3, wherein X is greater than or equal to about 4 mol. % and less than or equal to about 8 mol. %;
• and
• Y mol. % alkali oxide, wherein the alkali oxide comprises Na2O in an amount greater than or equal to about 9 mol. % and less than or equal to about 15 mol. %, a ratio of Y:X is greater than 1, and the glass composition is free of boron and compounds of boron, wherein the glass composition has a type HGA1 hydrolytic resistance according to ISO 720.