From Halopedia, the Halo wiki
Zinc, chemical symbol Zn, is a moderately reactive, bluish grayish metal that tarnishes in moist air and burns in air with a bright bluish-green flame, giving off fumes of zinc oxide. It reacts with acids, alkali's and other non-metals. If not completely pure, zinc reacts with dilute acids to release hydrogen. The one common oxidation state of zinc is +2. From 100°C to 210°C (212°F to 410°F) zinc metal is malleable and can easily be beaten into various shapes. Above 210°C (410°F), the metal becomes brittle and will be pulverized by beating. Zinc is nonmagnetic. In nonscientific text zinc is also referred to as "spelter."
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