Lapilli (nonfiction)

Lapilli samples, ranked by size.

Lapilli is a size classification term for tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts.

Lapilli (singular: lapillus) means "little stones" in Latin.

By definition lapilli range from 2 to 64 mm (0.08 to 2.52 in) in diameter.

A pyroclastic particle greater than 64 mm in diameter is known as a volcanic bomb when molten, or a volcanic block when solid.

Pyroclastic material with particles less than 2 mm in diameter is referred to as volcanic ash.

Lapilli are spheroid, teardrop, dumbbell- or button-shaped droplets of molten or semi-molten lava ejected from a volcanic eruption that fall to earth while still at least partially molten.

These granules are not accretionary, but instead the direct result of liquid rock cooling as it travels through the air.

Fiction cross-reference

• Lapilli soup - soup made from lapilli

Nonfiction cross-reference

• Tephra (nonfiction)

External links:

• Lapilli @ Wikipedia