Glass in the form of faience appears in Egypt as far back as the Neolithic Baderian culture (fifth to the fourth millennium BC). The knowledge of glassmaking was probably introduced from the Near East and first appears in Egypt around the eighteenth Dynasty (about 1550 – 1292 BC). Most early glass objects were beads. Glass was a luxury item during the New Kingdom and made into vases and inlays for furniture and wall decorations.
The melting temperature of pure silica is too high for ancient manufacture, but the addition of an alkali such as soda or potash lowers the temperature for melting. Lime would have been added to stabilize the mixture. To make raw glass, the ancient Egyptians would have ground the materials as fine as possible before heating it. Ancient glass was tinted by adding pigments to the raw glass, such as copper or iron compounds for a greenish blue color, copper oxides for red or orange, or cobalt compounds for dark blue.
The most common way to produce glass in the New Kingdom was through core-forming. A core in the shape of the interior of the vessel was formed from clay mixed with dung or plant materials. This core was dipped in molten glass or the molten glass was poured over it. The object was then rolled over a hard surface to make it smooth. After it was cooled, the clay mixture was removed. Molding was another glass forming technique, in which molten glass was poured in a mold or ground glass was heated in a mold. Cold cutting treated a block of glass as a block of stone, but this method was difficult and not common.
In Ptolemaic and Roman Egypt, glass was more widely used for everyday objects such as dishes and plates, bowls, cups, lamps, pendants or inlays in jewelry, or as mirrors. Around the third century AD, the lusterware technique was developed in Roman Egypt. Silver and copper alloys were added to pigments painted on glass. The pigments fused into the glass and created darker or lighter colors depending on the firing temperature. By the Coptic period, molded glass bowls began to appear.
After Amr Bin Alas conquered Egypt, the Arabs worked to further develop the glass-making industry and innovate many of the tools and techniques that were not known in previous periods. In glassblowing, the pontil, a solid metal rod used to hold the bottom of a vessel, became common in the early Islamic period. Other important glassblowing tools were wooden blocks, used to form the molten glass into a sphere prior to blowing; jacks, used to shape the mouth of the vessel; and shears, used to trim excess glass during blowing. Production of glass in the Islamic period used two types of molds. Glass could be blown into a two-part hinged mold with the pattern carved on the inside, usually with geometric and plant-like designs. Molten glass was also blown into the dip mold, but then removed and further inflated, which would make the pattern less distinct.
The glass of the Islamic period is distinguished by elaborate ornamentation coupled with calligraphy of Qur'anic verses and other writings. Several techniques were used to decorate glass. The hot-worked technique used a glass vessel that was still warm. Metal tongs with a carved pattern were stamped on a vessel or trails of hot glass were poured over the vessel to form a spiral pattern. The trails were combed with a toothed tool into wavy, arched, or festooned patterns. Blown glass was also decorated by cutting techniques including scratch-engraved, facet cut, and relief-cut. Stained or luster-painted glass was painted with pigments containing silver and copper and then fired to fuse the colors to the glass. To make enameled and gilded glass, gold and powdered opaque glass were applied to the surface of a previously formed vessel that was then fired.