Until recently, Greenland possessed the oldest known rocks in the world. They date back 3.7 billion years (SN: 12/9/72, p. 374). Now granite and crystalline schist specimens … suggest that the Antarctic Continent is older. These specimens date back 4 billion years.
At about 4.3 billion years old, bedrock in northeastern Canada currently holds the title of oldest known rock on Earth (SN: 4/15/17, p. 8). In Western Australia, scientists have found zircon crystals in bedrock that are even older, dating to about 4.4 billion years ago. For comparison, Earth is only about 4.5 billion years old.