A spark plug (100; 110) for an internal combustion engine, the spark plug (100; 110) comprising: an elongated center electrode having a center electrode tip at a first end and a terminal proximate a second end opposite the first end; an insulator surrounding at least a portion of the center electrode; and an outer shell surrounding at least a portion of the insulator; wherein the insulator comprises: a first segment surrounding at least a portion of the terminal, a second segment extending from the first segment, a third segment extending from the second segment, wherein a gap is disposed between the third segment of the insulator and the outer shell such that at least a portion of the third segment of the insulator is exposed to a combustion chamber when the spark plug (100; 110) is disposed within an internal combustion engine, and a coating (101; 111) applied to at least a portion of the third segment, wherein the coating (101; 111) is formed of a first layer (102; 112) disposed on at least a portion of a surface of the third segment and a second layer (104; 114) disposed on at least a portion of the first layer (102; 112), charaterised in that each of the first (102; 112) and second (104; 114) layers is formed of one or more glaze materials which include a refractory powder selected from the group consisting of a high temperature ceramic powder, alumina, zirconium oxide (ZrO 2), mullite, yittrium oxide (Y 2 O 3), magnesium oxide (MgO), lanthium oxide (La 2 O 3), boron nitride, aluminum nitride (AlN), and combinations thereof. an elongated center electrode having a center electrode tip at a first end and a terminal proximate a second end opposite the first end; an insulator surrounding at least a portion of the center electrode; and an outer shell surrounding at least a portion of the insulator; wherein the insulator comprises: a first segment surrounding at least a portion of the terminal, a second segment extending from the first segment, a third segment extending from the second segment, wherein a gap is disposed between the third segment of the insulator and the outer shell such that at least a portion of the third segment of the insulator is exposed to a combustion chamber when the spark plug (100; 110) is disposed within an internal combustion engine, and a coating (101; 111) applied to at least a portion of the third segment, wherein the coating (101; 111) is formed of a first layer (102; 112) disposed on at least a portion of a surface of the third segment and a second layer (104; 114) disposed on at least a portion of the first layer (102; 112), charaterised in that each of the first (102; 112) and second (104; 114) layers is formed of one or more glaze materials which include a refractory powder selected from the group consisting of a high temperature ceramic powder, alumina, zirconium oxide (ZrO 2), mullite, yittrium oxide (Y 2 O 3), magnesium oxide (MgO), lanthium oxide (La 2 O 3), boron nitride, aluminum nitride (AlN), and combinations thereof. a first segment surrounding at least a portion of the terminal, a second segment extending from the first segment, a third segment extending from the second segment, wherein a gap is disposed between the third segment of the insulator and the outer shell such that at least a portion of the third segment of the insulator is exposed to a combustion chamber when the spark plug (100; 110) is disposed within an internal combustion engine, and a coating (101; 111) applied to at least a portion of the third segment, wherein the coating (101; 111) is formed of a first layer (102; 112) disposed on at least a portion of a surface of the third segment and a second layer (104; 114) disposed on at least a portion of the first layer (102; 112), charaterised in that each of the first (102; 112) and second (104; 114) layers is formed of one or more glaze materials which include a refractory powder selected from the group consisting of a high temperature ceramic powder, alumina, zirconium oxide (ZrO 2), mullite, yittrium oxide (Y 2 O 3), magnesium oxide (MgO), lanthium oxide (La 2 O 3), boron nitride, aluminum nitride (AlN), and combinations thereof.