Question

1. which of the following is a metallic mineral?

a. quartz (sio₂)
b. sulfur (s)
c. copper (cu)
d. gypsum

1. what is a native element?

a. a mineral that forms through contact metamorphism
b. a pure metal found naturally in earths crust
c. a mineral composed of two or more elements
d. a mineral that forms from hydrothermal solutions

Explanation:

1. Quartz is a non - metallic mineral (silicate), sulfur is a non - metal element (not a metallic mineral in the traditional sense for metallic minerals in geology which are often metals like copper), gypsum is a non - metallic sulfate mineral. Copper is a metallic mineral.
2. A native element is a pure element (metal, semi - metal, or non - metal) that occurs naturally in its uncombined form. Option b correctly defines a native element (a pure metal found naturally in Earth's crust). Option a is about a mineral formation process (contact metamorphism), option c is a general description of a mineral (most minerals are composed of two or more elements), option d is about a mineral formation process (hydrothermal solutions).

Answer:

1. c. Copper (Cu)
2. b. A pure metal found naturally in Earth’s crust