Continental Crust (SIAL)
Forms continents and their shelves
Up to 70 km thick in mountain ranges
Density=2.7
Age-up to 3700
Granitic crust
Rich in silicon and Aluminium
REMEMBER: OBESE COMPUTER NERD – less dense [nerd], thick [fat], older


Oceanic Crust (SIMA)
Forms deep sea [ocean] floor
Average thickness of 6 km
Density=3.0
Age-up to 220
Basaltic crust
Rich in silicon and Magnesium
REMEMBER: Anorexic BABY – dense[dumb], young, thin – babies say ‘ma’ for MAgnesium and siMA. Begins with the letter B –basaltic crust




So to answer your question in brief, it's silicon, then aluminium

Edit
It's definitely not granite!
Yes, well actually its silicon compounds, which are called silicates

Silicates!

granite

are you doing the pangea project that every person i know in middle school is doing? because everybody always has the same questions as me. well mine is due tmrw & i just found the anwer to your question so i'll tell you.
Continental plates are mainly made up of granite rock and also has some aluminum and silica in it too.

Granite is not a mineral; it's a rock. A rock that is made of feldspars, which are the most common minerals in continental crust.