Glassmaking was accidentally discovered by potters around 3000 B.C. and the technique of glass blowing was invented around 100 B.C.
The first glass made in North America was in Mexico in 1535 by artisans brought by the Spanish from Europe. Although these original glassworks were short lived, glassblowing was reintroduced into Mexico hundreds of years ago and flourished, due largely to the simplicity of the ingredients and the ingenuity of the Mexican arts and crafts tradition.
Today Mexico is well known for rustic handblown drinking glasses, many of them characterized by a cobalt blue band at the rim.
To create different colours, various metal oxides are added. Small amounts of iron and sulphur will achieve amber and brown effects while green and aqua glasses require iron.
Light blues need copper, while dark blues contain very small quantities of cobalt. Pastel colours can also be achieved by adding crushed glass of the desired colour.