Take a look at the graphite of a pencil and you will see that it is dark gray and shiny like a metal. For thousands of years it was mistaken for lead and was referred to as “plumbago,” or “black lead,” hence the use of the term “lead” to refer to the graphite used in a pencil. The confusion is understandable since they are both soft metals (although these days we call graphite a semi-metal). Plumbago mines became more and more valuable as new uses were found for graphite, such as the discovery that it was the perfect material to cast cannon and musket balls. In seventeenth- and
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