The recipe for making glass has changed little for several thousands of years: sand, alkali ashes, and lime from crushed stones are melted together to give a strong, yet fragile material. This molten material can then be manipulated by the glassmaker in a number of ways.This 19th century, English goblet was created by free blowing. This is where air is blown down a metal tube that has a blob of glass at its end to create a bubble. This bubble of glass is then shaped using a variety of tools to create the desired form.It is made out of white opaque glass which gets its colour from tin oxide. White opaque glass became popular with the demand in the 17th and 18th centuries for porcelain from China and later from European factories.