A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO.sub.2, 0 to 20% Al.sub.2O.sub.3, 12 to 23% MgO, 0 to 4% Li.sub.2O, 0 to 10% Na.sub.2O, 0 to 10% K.sub.2O, 0 to 5% ZrO.sub.2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na.sub.2O+Li.sub.2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO.sub.2, 0 to 20% Al.sub.2O.sub.3, 12 to 23% MgO, 0 to 4% Li.sub.2O, 0 to 10% Na.sub.2O, 0 to 10% K.sub.2O, 0 to 5% ZrO.sub.2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na.sub.2O+Li.sub.2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

A coated glass or glass ceramic substrate includes a substrate with a surface area and a coating on that surface area. The coating includes a glass matrix and IR-reflecting pigments. The IR-reflecting pigments have a TSR value of at least 20%, as determined according to ASTM G 173. The coating, at a wavelength of 1500 nm, exhibits a remission of at least 35%, as measured according to ISO 13468.

A coated glass or glass ceramic substrate includes a substrate with a surface area and a coating on that surface area. The coating includes a glass matrix and IR-reflecting pigments. The IR-reflecting pigments have a TSR value of at least 20%, as determined according to ASTM G 173. The coating, at a wavelength of 1500 nm, exhibits a remission of at least 35%, as measured according to ISO 13468.

Gradient refractive index (GRIN) materials can include multi-phase composites having substances with differing refractive indices disposed non-uniformly within one another. Particular glass composites having a gradient index of refraction can include: an amorphous phase, and a phase-separated region disposed non-uniformly within the amorphous phase. The glass composites include a mixture containing: GeZ.sub.2 and A.sub.2Z.sub.3 in a combined molar ratio of about 60% to about 95%, and CsX and PbZ in a combined molar ratio of about 5% to about 40%, where A is As, Sb or Ga, X is Cl, Br or I, and Z is S or Se. When A is As, the glass composites include PbZ in a molar ratio of about 15% or less. The amorphous phase and the phase-separated region have refractive indices that differ from one another. More particularly, A is Ga or As, X is Cl, and Z is Se.

Gradient refractive index (GRIN) materials can include multi-phase composites having substances with differing refractive indices disposed non-uniformly within one another. Particular glass composites having a gradient index of refraction can include: an amorphous phase, and a phase-separated region disposed non-uniformly within the amorphous phase. The glass composites include a mixture containing: GeZ.sub.2 and A.sub.2Z.sub.3 in a combined molar ratio of about 60% to about 95%, and CsX and PbZ in a combined molar ratio of about 5% to about 40%, where A is As, Sb or Ga, X is Cl, Br or I, and Z is S or Se. When A is As, the glass composites include PbZ in a molar ratio of about 15% or less. The amorphous phase and the phase-separated region have refractive indices that differ from one another. More particularly, A is Ga or As, X is Cl, and Z is Se.

A translucent in-vivo indwelling device with a translucent region including a rare earth doped fluorapatite.

A translucent in-vivo indwelling device with a translucent region including a rare earth doped fluorapatite.

An article comprises a body having a coating. The coating comprising a mixture of a first oxide and a second oxide. The coating includes a glaze on a surface of the coating, the glaze comprising a eutectic system having a super-lattice of a first fluoride and a second fluoride.

An article comprises a body having a coating. The coating comprising a mixture of a first oxide and a second oxide. The coating includes a glaze on a surface of the coating, the glaze comprising a eutectic system having a super-lattice of a first fluoride and a second fluoride.