The constants in making glass tiles, or anything else glass, are a mix of silica and potassium or sodium chloride and varying degrees of heat or fire applied. Smalti tiles have metals and metal oxides added to the mix to produce rich colors and flecks. After firing, the glass is cut into tiles. Another type, fused tiles, are made by cutting float glass into tiles, adding color either above or below them, and firing it.
Slump tiles are made from molten plate glass that is poured into a mold to raise patterns. Sintered tiles are similar but the process involves putting a glass powder into a die and heated. In both these types color is added either before or during the firing. Glass bottles can be recycled into tiles by crushing the bottles, placing the pieces into molds and firing them to where they melt into each other.
Considering that museums have intact pieces of early glass dating back 4,000 years, 21st century consumers realize that glass is a durable material. Of course, it will shatter if hit hard by a sharp object, but it bears up extremely well under normal foot traffic in your home. The American Society for Testing Materials has put it to the test and found that it can hold up to 420 lbs.
Glass has the innate quality of being able to reflect light, which makes handmade glass tile floors ideal for areas in your home that need it. Their versatility is limited only by the artistry of art glass artisans all over the world that are constantly coming up with new colors and applications and will create designs uniquely for you.