Pele's tears

Pele’s tears is a geological term for small pieces of solidified lava drops formed when airborne particles of molten material fuse into tearlike drops of volcanic glass. Pele’s tears are jet black in color and are often found on one end of a strand of Pele's hair. Pele's tears is primarily a scientific term used by volcanologists.

Pele's tears, like Pele's hair, is named after Pele, the Hawaiian fire goddess of volcanoes.

Lava fountains produce spectacular displays of volcanic activity with lava spurting out of the vent in a showering cascade of hot molten droplets. Many of the clots aggregate to form the familiar types of lava flows that we see in Hawaiian and Strombolian eruptions. However, there is also another interesting process that is occurring at the same time that is relatively unknown. This is the formation of glass spherules or droplets of solidified lava known as Pele’s tears. These are black in color and, as you can see from the photograph, they vary in shape and size.

The formation of these tears is a complex process depending on a number of different factors. Imagine a tiny droplet of lava being erupted from a lava fountain. Whilst it is travelling through the air two things are happening: It is cooling down very rapidly (a process known as quenching) and it is being deformed. The deformation of a droplet depends on the speed at which it is erupted from the volcano, its surface tension, the viscosity (thickness) of the magma and the resistance it experiences as it travels through the air.

Pele’s tears are also found entangled within fine strands of volcanic glass known as Pele’s hair and it was considered that they formed together under similar conditions. Shimozura (1994) investigated this further and found that the velocity of the erupting lava was the main factor in determining whether Pele’s tears or Pele's hair were formed. If the velocity of the erupting magma is high then Pele’s hair is formed and if the velocity is low the formation of Pele’s tears is favoured.

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