Explain why each mineral has its own set of unique physical features.?

Answer 1

If they didn't, we couldn't tell them apart and would call them the same mineral.

Answer 2

In order to distinguish one mineral from another, there has to be some unique physical feature distinguishing them.

Otherwise you can't tell them apart. And they are the same mineral.

Different minerals are made from various combinations and proportions of elements, that are arranged in various crystalline patterns.

So by definition, each mineral must have its own set of unique physical features. What people study and compare are exactly what the differences are ... sometimes it comes down to just the position of the atoms of the same element arranged in a different pattern. Diamond and graphite are the same element carbon, but with atoms in a different pattern. The difference of physical properties in this case, is enormous.

Answer 3

In most simple language, the properties of materials depend upon the bonding or arrangements of atoms into arrays of molecules.
Now for minerals, this bonding and arrangement in 3-D is under a definite crystallographic pattern. Each pattern or lattice gives definite properties to the minerals, same minerals have similar lattice.

It is the lattice and bonding basically between similar atoms or dissimilar atoms that form a lattice, which produces characteristic physical and optical properties in minerals. The chemical composition necessarily does not control these properties. Charcoal, graphite, diamond compositionally is pure carbon but with distinct properties, so is the case of quartz, chalcedony, agate, natural glass, they are compositionally silica but with very different properties.
Sometimes anomalous properties are induced through post formation pressure-temperature conditions (metamorphism) which distorts the lattice resulting in variation of properties. Another cause of variation in properties is due to solid solution or diadochy replacements or induction of non-essential atoms into the lattice at the time of formation. These are commonly known as “defects”.
Same way we build houses of different designs by using basic rectangular, cubic, triangular motifs. The strength of house or structure depends on the cementing or bonding we use to make it as far as a monolithic structure, any defect would induce “weakness” .
thnks

Answer 4

Each mineral is defined by its characteristic physical features. That definition is brought about by the fact that a mineral, basical, is a chemical compound, and the chemical compound has a consistent chemical composition, and a consisten crystalline form.