Final answer:
Minerals are naturally occurring, inorganic solids with a definite chemical composition and a unique crystalline structure. They have observable properties such as color, texture, and hardness for identification. Mineral composition and structure are crucial for determining their specific properties.
Step-by-step explanation:
The main characteristics that make a mineral include it being a naturally occurring, inorganic solid with a definite chemical composition and a unique crystalline structure. For a substance to be considered a mineral, it must not have been artificially created by humans; it should exist naturally. Minerals are typically composed of elements that are not associated with living organisms, making them inorganic. This distinguishes them from organic materials that are based on carbon molecules like those found in living things.
Minerals are always solids at room temperature, distinguishing them from elements or compounds that may exist as liquids or gases under normal conditions. The definite chemical composition is an essential aspect of minerals as it determines their specific properties, such as hardness and color
. This composition is reflected in a mineral's chemical formula, which is consistent for any given mineral, although some may have a range of compositions due to elemental substitution. The internal arrangement of atoms within a mineral determines its crystalline structure, which is visible on a macro level as the mineral's geometric shape or crystal habit.
Minerals can be identified by various observable properties such as color, texture, and hardness. Color is often the most noticeable characteristic but may not always be reliable for identification due to variations caused by impurities. The texture, whether coarse-grained, fine-grained, or foliated, and the mineral's ability to scratch glass provide additional clues to identification. Additionally, field identification of minerals often relies on observing light or dark colors and the presence of distinct crystal shapes or vesicles within volcanic rocks.