Pele's tears

Pele's tears (closest Hawaiian translation: "nā waimaka o pele") are 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, are named after Pele, the Hawaiian fire goddess of volcanoes. The formation of these tears is a complex process depending on a number of different factors as a tiny droplet of lava is 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. Under the microscope very tiny Pele's tears (less than 1 μm) can be found within the cavities of Pele's hair. This would suggest they formed prior to being trapped within the strand and supports a different mechanism for formation. It has been considered that they became trapped during transport in the eruptive plume. Pele's tears are interesting to volcanologists because trapped within the glass droplet are bubbles of gas and particles called vesicles. When these are analyzed they can provide a great deal of information about the mechanisms of an eruption.