Here's a breakdown:
* Granitic rocks: Rich in silica (SiO2), with abundant feldspar (especially potassium feldspar) and quartz. They are typically light-colored and have a high melting point.
* Basaltic rocks: Rich in magnesium and iron (mafic), with abundant pyroxene and olivine. They are typically dark-colored and have a lower melting point than granitic rocks.
Intermediate rocks fall in between these extremes. They have a silica content lower than granitic rocks but higher than basaltic rocks. They also have a wider range of mineral compositions, including:
* Andesite: A volcanic rock with a composition similar to diorite.
* Diorite: A plutonic rock with a composition similar to andesite.
* Gabbro: A plutonic rock with a composition similar to basalt.
Here's a helpful mnemonic to remember the order of increasing silica content:
Granite - Diorite - Andesite - Basalt
Important Note: While the composition of intermediate rocks falls between granitic and basaltic rocks, they have unique properties and uses. For example, andesite is often used in construction and landscaping.
