This shows a possible elongated fossilized Martian cell on the surface of a clay mineral which fills veins or cracks in the meteorite (NAKHLA). Other possible fossilized microbes are partly embedded in the clay mineral. This clay mineral is now known to have formed on Mars about 700 million years ago. If these embedded bumps are truly fossilized Martian microbes, they are then about 700 million years old. The elongated bump on the surface may have formed later or it may be the same age as the embedded bumps.