The oldest grain of sand found and dated is made of
A) zircon.
B) diamond.
C) peridotite.
D) basalt.

Question

Quizplus · Accepted Answer

The oldest grain of sand found and dated is made of zircon. Zircons have a crystalline structure that allows scientists to accurately determine their age through radiometric dating techniques. The oldest zircon grain found is estimated to be over 4.4 billion years old, making it one of the oldest known materials on Earth. Diamond, peridotite, and basalt are all common rocks and minerals found on Earth, but they are not typically used for radiometric dating of ancient materials.

The Oldest Grain of Sand Found and Dated Is Made