A diamond planet, "55 Cancri E", is a super-Earth exoplanet known for its high density and potential diamond composition. It is located 41 light-years away and is about twice the size of Earth and nine times its mass. The planet's extreme heat and pressure are believed to have crystallized its carbon-rich composition into diamonds.
Indeed there is a diamond planet that old too.
A diamond planet, "55 Cancri E", is a super-Earth exoplanet known for its high density and potential diamond composition. It is located 41 light-years away and is about twice the size of Earth and nine times its mass. The planet's extreme heat and pressure are believed to have crystallized its carbon-rich composition into diamonds.