How would the color and density of rock composed mostly of non-ferro magnesium silicate minerals differ from one made up mostly of ferro-magnesium silicate?

Answer 1

non-ferro magnesium silicate dominated rock would be lighter in color and less dense than ferro-magnesium silicate dominated rock.

NOTE: The color of olive-green belong to the ferro-magnesium silicate dominated rock group.

Answer 2

Rock composed mostly of non-ferro magnesium silicate minerals would likely have a lighter color and lower density compared to one made up mostly of ferro-magnesium silicate minerals. Non-ferro minerals tend to be less dense and have a more silicate-based composition, leading to lighter colors like white or gray. In contrast, ferro-magnesium silicate minerals often have higher iron content, resulting in darker colors like black or green and higher density.