The physical properties of minerals depend on what main factor?

The correct answer is based on the understanding that the physical properties of minerals are primarily determined by the internal arrangement and bonding of atoms within the mineral's structure. Each mineral is composed of specific elements that are arranged in a distinct crystal lattice, and this arrangement affects how the mineral interacts with light, its hardness, cleavage, and other physical characteristics.

For instance, minerals like diamond and graphite are both carbon-based but exhibit very different properties because of the way the carbon atoms are bonded and arranged. In diamond, each carbon atom is bonded to four others in a tetrahedral structure, resulting in a very hard mineral, whereas, in graphite, the carbon atoms are arranged in layers that can easily slide past one another, making it soft and lubricating.

While external environmental factors and geographical location can influence the formation and occurrence of minerals, they do not fundamentally alter the intrinsic physical properties that are controlled by atomic structure. Weathering processes might change the form or availability of certain minerals, but again, do not affect the basic physical properties defined by atomic arrangement. Thus, the internal arrangement and bonding of atoms is the primary factor influencing the physical properties of minerals.