Mafic rocks have low silica content.

Mafic rocks have low silica content.

• A. True
• B. False
• C. Sometimes
• D. Unknown

Answer: (A)

Silica content helps distinguish rock types by composition. Mafic rocks are dominated by magnesium- and iron-rich minerals, so they incorporate less silica overall than felsic rocks, which are rich in quartz and feldspar. In common examples, mafic rocks like basalt and gabbro sit around the 45–52% SiO2 range, while felsic rocks like rhyolite and granite are much higher, about 65–75% SiO2. Because of this established difference, the statement that mafic rocks have low silica content is accurate—their silica content is lower relative to felsic rocks.

Silica content helps distinguish rock types by composition. Mafic rocks are dominated by magnesium- and iron-rich minerals, so they incorporate less silica overall than felsic rocks, which are rich in quartz and feldspar. In common examples, mafic rocks like basalt and gabbro sit around the 45–52% SiO2 range, while felsic rocks like rhyolite and granite are much higher, about 65–75% SiO2. Because of this established difference, the statement that mafic rocks have low silica content is accurate—their silica content is lower relative to felsic rocks.