Q. Which of the following does not contain silicon?
A) Kaoline
B) Agate
C) Ruby
D) Quartz
Explanation
(c)
Ruby is mineral of aluminium $ie$, $Al_{2}O_{3}$.
It does not contain silicon.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.