A colored glass article includes greater than or equal to 50 mol % and less than or equal to 80 mol % SiO.sub.2; greater than or equal to 7 mol % and less than or equal to 25 mol % Al.sub.2O.sub.3; greater than or equal to 1 mol % and less than or equal to 15 mol % B.sub.2O.sub.3; greater than or equal to 5 mol % and less than or equal to 20 mol % Li.sub.2O; greater than or equal to 0.5 mol % and less than or equal to 15 mol % Na.sub.2O; greater than 0 mol % and less than or equal to 1 mol % K.sub.2O; and greater than or equal to 1×10.sup.−6 mol % and less than or equal to 1 mol % Au. R.sub.2O—Al.sub.2O.sub.3 is greater than or equal to −5 mol % and less than or equal to 7 mol %, R.sub.2O being the sum of Li.sub.2O, Na.sub.2O, and K.sub.2O.

A colored glass article includes greater than or equal to 50 mol % and less than or equal to 80 mol % SiO.sub.2; greater than or equal to 7 mol % and less than or equal to 25 mol % Al.sub.2O.sub.3; greater than or equal to 1 mol % and less than or equal to 15 mol % B.sub.2O.sub.3; greater than or equal to 5 mol % and less than or equal to 20 mol % Li.sub.2O; greater than or equal to 0.5 mol % and less than or equal to 15 mol % Na.sub.2O; greater than 0 mol % and less than or equal to 1 mol % K.sub.2O; and greater than or equal to 1×10.sup.−6 mol % and less than or equal to 1 mol % Au. R.sub.2O—Al.sub.2O.sub.3 is greater than or equal to −5 mol % and less than or equal to 7 mol %, R.sub.2O being the sum of Li.sub.2O, Na.sub.2O, and K.sub.2O.

A process for the preparation of multi-coloured dental restorations is described, in which glasses and glass ceramics with various compositions are given the shapes of dental restorations and colour changes are effected in the glasses and glass ceramics by irradiating them with artificial electromagnetic radiation and subjecting them to a heat treatment.

A process for the preparation of multi-coloured dental restorations is described, in which glasses and glass ceramics with various compositions are given the shapes of dental restorations and colour changes are effected in the glasses and glass ceramics by irradiating them with artificial electromagnetic radiation and subjecting them to a heat treatment.

The present invention relates to a glass for a pharmaceutical container that is excellent in ultraviolet shielding ability, and is also excellent in chemical durability. The glass for a pharmaceutical container of the present invention includes as a glass composition, in terms of mass %, 67% to 81% of SiO.sub.2, more than 4% to 7% of Al.sub.2O.sub.3, 7% to 14% of B.sub.2O.sub.3, 3% to 12% of Na.sub.2O+K.sub.2O, 0% to 1.8% of CaO+BaO, 0.5% to less than 2% of Fe.sub.2O.sub.3, and 1% to 5% of TiO.sub.2, and satisfies a relationship of CaO/BaO≤0.5.

The present invention relates to a glass for a pharmaceutical container that is excellent in ultraviolet shielding ability, and is also excellent in chemical durability. The glass for a pharmaceutical container of the present invention includes as a glass composition, in terms of mass %, 67% to 81% of SiO.sub.2, more than 4% to 7% of Al.sub.2O.sub.3, 7% to 14% of B.sub.2O.sub.3, 3% to 12% of Na.sub.2O+K.sub.2O, 0% to 1.8% of CaO+BaO, 0.5% to less than 2% of Fe.sub.2O.sub.3, and 1% to 5% of TiO.sub.2, and satisfies a relationship of CaO/BaO≤0.5.

A glass-ceramic that includes a first crystal phase including (Mg.sub.xZn.sub.1-x)Al.sub.2O.sub.4, where x is ≤1, and a second crystal phase including tetragonal ZrO.sub.2. The glass-ceramic may be substantially free of arsenic, tin, antimony, and cesium, each of the arsenic, tin, antimony, and cesium present at less than 0.01% (by mole of oxide). Further, the glass-ceramic may include a transmittance of at least about 80% to light having a wavelength of 380 nm to 760 nm.

A glass-ceramic that includes a first crystal phase including (Mg.sub.xZn.sub.1-x)Al.sub.2O.sub.4, where x is ≤1, and a second crystal phase including tetragonal ZrO.sub.2. The glass-ceramic may be substantially free of arsenic, tin, antimony, and cesium, each of the arsenic, tin, antimony, and cesium present at less than 0.01% (by mole of oxide). Further, the glass-ceramic may include a transmittance of at least about 80% to light having a wavelength of 380 nm to 760 nm.

A colored glass article includes greater than or equal to 50 mol % and less than or equal to 70 mol % SiO.sub.2, greater than or equal to 10 mol % and less than or equal to 17.5 mol % Al.sub.2O.sub.3, greater than or equal to 3 mol % and less than or equal to 10 mol % B.sub.2O.sub.3, greater than or equal to 8.8 mol % and less than or equal to 14 mol % Li.sub.2O, greater than or equal to 1.5 mol % and less than or equal to 8 mol % Na.sub.2O, and greater than 0 mol % and less than or equal to 2 mol % Cr.sub.2O.sub.3. R.sub.2O+RO−Al.sub.2O.sub.3 is greater than or equal to 0.5 mol % and less than or equal to 6 mol %. Al.sub.2O.sub.3+MgO+ZnO is greater than or equal to 12 mol % and less than or equal to 22 mol %.

A colored glass article includes greater than or equal to 50 mol % and less than or equal to 70 mol % SiO.sub.2, greater than or equal to 10 mol % and less than or equal to 17.5 mol % Al.sub.2O.sub.3, greater than or equal to 3 mol % and less than or equal to 10 mol % B.sub.2O.sub.3, greater than or equal to 8.8 mol % and less than or equal to 14 mol % Li.sub.2O, greater than or equal to 1.5 mol % and less than or equal to 8 mol % Na.sub.2O, and greater than 0 mol % and less than or equal to 2 mol % Cr.sub.2O.sub.3. R.sub.2O+RO−Al.sub.2O.sub.3 is greater than or equal to 0.5 mol % and less than or equal to 6 mol %. Al.sub.2O.sub.3+MgO+ZnO is greater than or equal to 12 mol % and less than or equal to 22 mol %.