'This dark volcanic rock is low in silica content but fairly rich in iron & magnesium'
basalt
B IN SCIENCE: This dark volcanic rock is low in silica content but fairly rich in iron & magnesium
This dark volcanic rock is low in silica content but fairly rich in iron & magnesium
This dark volcanic rock is low in silica content but fairly rich in iron & magnesium
"B" IN SCIENCE
basalt
"B" IN SCIENCE