* Minerals are naturally occurring, solid substances with a definite chemical composition and crystal structure. Gases, by their very nature, are not solid.

* Volcanic gases are primarily composed of volatile compounds, like water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen sulfide (H2S), and others. While some of these compounds can be found in mineral form (like water in ice or carbon dioxide in calcite), they exist in gaseous form within the volcano.

However, some volcanic gases can interact with the environment to form minerals. For example, sulfur dioxide can react with atmospheric water to form sulfuric acid, which can then contribute to the formation of secondary minerals like gypsum.

So, while the gases themselves are not minerals, they can play a role in the formation of minerals in other processes.