High Quality Content by WIKIPEDIA articles! Porous glass is glass that includes pores, usually in the nm- or µm-range, commonly prepared by one of the following processes: 1) metastable phase separation in borosilicate glasses (such as in the system SiO2-B2O3-Na2O), followed by liquid extraction of one of the formed phases; 2) the sol-gel process; or 3) simply by sintering glass powder. The specific properties and commercial availability of porous glass make it one of the most extensively researched and characterized amorphous solids.