"Many people have assumed that the hematite in ancient rocks formed by the oxidation of siderite in the modern atmosphere," said Hiroshi Ohmoto, professor of geochemistry, Penn State.

The team’s analyses of hematite-containing samples from Australia’s Marble Bar Chert — a rock formation in the northwestern part of the country — suggest the hematite formed deep ...

The first chemical analysis of the tiny spherules of rock called Martian blueberries shows that they are composed of iron-bearing hematite -- a finding that provides yet another piece of evidence ...

In a study published June 17 in the journal Nature, the Utah researchers suggest both the Martian and Utah rocks formed underground when minerals precipitated from flowing groundwater. Advanced Search ...

On Mars, most of the hematite rocks are about 0.16 inches (4 millimeters) in diameter, and no larger than 0.24 inches (6.2 millimeters). By contrast, Earth spherules exhibit a large range of sizes ...

Scientists once believed our planetary next-door neighbor got its rusty hue from hematite, a common iron ore known for its ...

As the foremost source of iron ores on the planet, hematite has shaped civilizations for thousands of years. The mineral was first used as the main pigment in cave paintings often having a reddish ...

Discovering that Mars’ hue may be due to a water-containing rusty mineral like ferrihydrite, as opposed to hematite’s waterless form of rust, surprised the researchers, Valantinas said.

This jasper or hematite-rich chert formed in ways similar to the way this rock forms around hydrothermal vents in the deep oceans today. "Many people have assumed that the hematite in ancient ...

“Many people have assumed that the hematite in ancient rocks formed by the oxidation of siderite in the modern atmosphere,” said Hiroshi Ohmoto, professor of geochemistry, Penn State.