Lithium silicate glasses or glass ceramics with the following composition: 50 to 70 wt-% SiO 2 , 15 to 22 wt-% Li 2 O, 8 to 20 wt-% of a stabilizer selected from ZrO 2 and/or HfO 2 , 0,1 to 4 wt-% K 2 O and/or Na 2 O, 0,1 to 4 wt-% Al 2 O 3 , and 2 to 8 wt-% additives, with the proviso that the glasses or glass ceramics do not have one of the following compositions 69,8 wt-% SiO 2 60,5 wt-% SiO 2 16,0 wt-% Li 2 O 15,0 wt-% Li 2 O 8,6 wt-% ZrO 2 13,3 wt-% ZrO 2 2,0 wt-% K 2 O 3,3 wt-% K 2 O 0,2 wt-% Al 2 O 3 2,9 wt-% Al 2 O 3 3,3 wt-% P 2 O 5 5,0 wt-% P 2 O 5 0,1 wt-% VO 2 wherein the additives are selected from the group consisting of - nucleating agents selected from the group consisting of phosphorous oxide, titanium oxide, tin oxide, noble metals, and mixtures thereof, - fluorescent agents selected from the group consisting of oxides of rare earth elements, and mixtures thereof, - glass colouring oxides selected from the group of oxides of iron, titanium, cerium, copper, chromium, cobalt, nickel, manganese, selenium, silver, indium, gold, vanadium, rare earth elements, and mixtures thereof, - doped spinels, and - mixtures thereof, and/or the additives are selected from the group consisting of boron oxide, fluorine, barium oxide, strontium oxide, magnesium oxide, zinc oxide, calcium oxide, yttrium oxide, titanium oxide, niobium oxide, tantalum oxide, lanthanum oxide and mixtures thereof. 50 to 70 wt-% SiO 2 , 15 to 22 wt-% Li 2 O, 8 to 20 wt-% of a stabilizer selected from ZrO 2 and/or HfO 2 , 0,1 to 4 wt-% K 2 O and/or Na 2 O, 0,1 to 4 wt-% Al 2 O 3 , and 2 to 8 wt-% additives, with the proviso that the glasses or glass ceramics do not have one of the following compositions 69,8 wt-% SiO 2 60,5 wt-% SiO 2 16,0 wt-% Li 2 O 15,0 wt-% Li 2 O 8,6 wt-% ZrO 2 13,3 wt-% ZrO 2 2,0 wt-% K 2 O 3,3 wt-% K 2 O 0,2 wt-% Al 2 O 3 2,9 wt-% Al 2 O 3 3,3 wt-% P 2 O 5 5,0 wt-% P 2 O 5 0,1 wt-% VO 2 wherein the additives are selected from the group consisting of - nucleating agents selected from the group consisting of phosphorous oxide, titanium oxide, tin oxide, noble metals, and mixtures thereof, - fluorescent agents selected from the group consisting of oxides of rare earth elements, and mixtures thereof, - glass colouring oxides selected from the group of oxides of iron, titanium, cerium, copper, chromium, cobalt, nickel, manganese, selenium, silver, indium, gold, vanadium, rare earth elements, and mixtures thereof, - doped spinels, and - mixtures thereof, and/or - nucleating agents selected from the group consisting of phosphorous oxide, titanium oxide, tin oxide, noble metals, and mixtures thereof, - fluorescent agents selected from the group consisting of oxides of rare earth elements, and mixtures thereof, - glass colouring oxides selected from the group of oxides of iron, titanium, cerium, copper, chromium, cobalt, nickel, manganese, selenium, silver, indium, gold, vanadium, rare earth elements, and mixtures thereof, - doped spinels, and - mixtures thereof, the additives are selected from the group consisting of boron oxide, fluorine, barium oxide, strontium oxide, magnesium oxide, zinc oxide, calcium oxide, yttrium oxide, titanium oxide, niobium oxide, tantalum oxide, lanthanum oxide and mixtures thereof. <EOS>