Cementation process in the 1740s. In the early modern period, brass, an alloy of copper and zinc, was usually produced by a cementation process in which metallic copper was heated with calamine, a zinc ore, to make calamine brass. Cementation process The cementation process is an obsolete technology for making steel by carburization of iron. Unlike modern steelmaking, it increased the amount of carbon in the iron. It was apparently developed before the 17th century. Derwentcote Steel Furnace, built in 1720, is the earliest surviving example of a cementation furnace. Another example in the UK is the cementation furnace in Doncaster Street,
Metallic color the metallic finish of such paints was added using fine aluminum powder and pigment rather than actual gold. The use of metallic colors is not limited to those colors that approximate the appearance of actual metals. In some instances, it has been noted, "[b]eetles with bright metallic colors are made up into tie pins and cuff links". One popular modern use of metallic colors is for automobiles, which use metallic paint to achieve a particular shine. Such colors "are made from a combination of different pigments and aluminum flakes that have different weights and particle sizes". Crayon-maker Crayola has manufactured