Chemical reactions deep inside the Earth fuel magma’s gem-laden upward journey
Drop a Mentos candy in a bottle of Diet Coke, and carbon dioxide will bubble violently out of the soda. Similar chemical reactions may send certain kinds of magma frothing up from deep within the Earth, carrying diamonds along the way.
The discovery, reported in the Jan. 19 Nature, solves several mysteries about why and how diamond-bearing rocks appear where they do. As gem-laden magma rises, the theory goes, it gobbles a mineral called orthopyroxene, changing the magma’s chemical composition and belching carbon dioxide gas that drives its continued ascent.
“We’ve provided a simple, chemically reasonable process to have dissolved gas