Zinc
Zinc is an element, number 30 on the periodic table. 

When James T. Kirk asked Spock whether he could build some form of computer in 1930 to pinpoint Doctor McCoy's location and date of arrival in that year, Spock voiced his skepticism by answering "In this zinc-plated vacuum tubed culture?" ()

Zinc and copper could be combined into an alloy to form brass.

External link
 

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Elements