Discoveries made by NASA’s Curiosity rover have been baffling scientists on earth since it landed on the Red Planet in 2012. Now, the car-sized robotic rover has spotted silica on the Red Planet, NASA announced.

The silica has been found in high concentrations. Adding to that, Curiosity has also found a mineral, which is even very rare on earth and never seen before on Mars, the space agency added. The mineral named tridymite has been discovery by the rover while drilling into a rock called ‘Buckskin’.

The mysterious findings led scientists to take the new step of ordering the rover to retrace its path to learn more about the mineral and silica. Jens Frydenvang from Los Alamos National Laboratory and the University of Copenhagen said the discovery is surprising because presence of silica is linked to water. On our home planet, high levels of silica are associated with environments that support microbial life, Frydenvang explained.

Albert Yen, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, said in a statement that the new high-silica compositions are baffling scientists. There are only two possible ways to boost silica concentration: add silica by using other sources or by stripping away other materials.

“"Either of those processes involves water. If we can determine which happened, we'll learn more about other conditions in those ancient wet environments”, Yen added. Talking about tridymite on Mars, NASA said the mineral’s origin on earth needs high temperatures in metamorphic rocks.