category 1
What is the hardest naturally occurring mineral?
Diamond, with hardness 10 on the Mohs Scale.
Which mineral is known for its purple color and is a variety of quartz?
Amethyst.
Which mineral is used as the minimum hardness reference (grade 1) on the Mohs Scale?
Talc.
What is "luster" in mineralogy?
It is how light reflects off a mineral's surface, which can be metallic or non-metallic (vitreous, silky, etc.).
What is the most abundant mineral in the Earth's crust?
Feldspar (especially plagioclase).
Which mineral is the main source of aluminum?
Bauxite (actually a rock composed of minerals like gibbsite, boehmite, and diaspore).
Which mineral is the main source of iron?
Hematite.
What scientifically defines a mineral?
It is a natural, inorganic substance with a defined chemical composition and organized crystalline structure.
What property describes how a mineral breaks?
Cleavage (when it breaks along flat surfaces) or fracture (when it doesn't follow a pattern).
Which mineral is known for its natural magnetic properties?
Magnetite