The temperature of magma rising to the surface of Earth is a crucial factor in whether or not molten rock will glow red, orange, yellow or white. As temperatures increase, so does the amount of radiation emitted by the molten rock.
When magma reaches 525 degrees Celsius (925 degrees Fahrenheit), it begins to glow red. However, hotter lavas become orange or even yellow as they warm.
In the case of the eruption of Kilauea in Hawaii, lava that exploded out of the volcano was at a temperature of 1,170 degrees Celsius (2,140 degrees Fahrenheit). The lava then traveled down tubes to the sea where it was still hot enough to vaporize a car!
Technically, lava can be blue, but it cannot reach the temperatures required for black-body emission. For lava to be considered blue, it would have to rise up to at least 6,000 degrees Celsius, which is far, far above any of the naturally occurring temperatures on Earth's surface.
Many materials can withstand the high temperatures of lava, from metals like titanium, iron alloys, tungsten, molybdenum, iridium and osmium to ceramics such as aluminum oxide, silicon nitride and mullite.
Pillow Lava is a type of lava that forms when lava flows out of the Earth's crust underwater. These pillows are usually about a meter across and can be formed under water or on mid-ocean ridges.