Hard metallic elements are substances that are solid at room temperature and have a high melting point. Rhodium is a rare, silvery-white metal that is highly resistant to corrosion and oxidation. It is often used in jewelry and as a catalyst in chemical reactions. ZINC is a bluish-white metal that is also resistant to corrosion and oxidation. It is commonly used in galvanizing, which is the process of coating steel or iron with ZINC to protect it from rust.