Is a rock that cools quickly after lava rusted through a volcano what is the best description of its texture

The physical description would be soft due to the lava cooling the rock.

I think glass. Where does rust play a part of lava?

answer and explanation;

composition refers to both the types of minerals within a rock and the overall chemical makeup of the rock while texture refers to the size and arrangement of the minerals or grains that make up a rock. both composition and texture can be used to classify rocks, such as igneous rocks. texture describes how the rock became solid or crystallized from liquid, melted rock. composition of a rock describes the minerals that make up a particular rock.

If your workout exceeds an hour you should substitute "a sports drink" for water.hope my answer has you : )