Pele's hair

Pele's hair is a form of lava. It is named after Pele, the Hawaiian goddess of volcanoes. It can be defined as volcanic glass fibers or thin strands of volcanic glass. The strands are formed through the stretching of molten basaltic glass from lava, usually from lava fountains, lava cascades, and vigorous lava flows.

Pele's hair is extremely light, so the wind often carries the fibers high into the air and to places several kilometers away from the vent. It is common to find fibers of Pele's hair on high places like top of trees, radio antennas, and electric poles.

Pele's hair does not only occur in Hawaii. It can be found near other volcanoes around the world, for example in Nicaragua (Masaya), Italy (Etna) and Ethiopia (Erta’ Ale). It is usually found in gaps in the ground, mostly near vents, skylights, ocean entry, or in corners where Pele's hair can accumulate.

It is not recommended to touch Pele's hair, because it is very brittle and very sharp, and small broken pieces can enter the skin. Gloves should be worn while examining it.

Pele's tears might occur with Pele's hair. They can tell volcanologists a lot of information about the eruption, such as the temperatures and the magma's path to the surface. Plagioclase starts to crystallize from the magma of Pele's hair at around 1,160 °C. Also, the shape of the tears can provide an indication of the velocity of the eruption, and the bubbles of gas and particles trapped within the tears can provide information about the composition of the magma chamber.

The formation of Pele's hair occurs when molten basaltic glass is blowing-out from lava. The strands are created when molten lava is ejected into the air and form tiny droplets, which elongate perfectly straight. It usually forms in lava fountains, lava cascades, and vigorous lava flows.

Pele's hair has a golden yellow color and looks like human hair. It also looks like straw. In sunlight, it has a shimmering gold color. The lengths can vary a lot, but it has an average of 2 to 6 inch length. A particular strand can have a diameter of less than 0.5 mm, and be 2 m long. It is extremely light.

A manufactured version of Pele's hair made from basalt rock and recycled slag from steel manufacturing called mineral wool or stone wool is commonly used as a non-combustible, durable, dimensionally stable, UV stable, hydrophobic, vapour-permeable building insulation for residential, commercial, and high rise buildings.

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Wikipedia