stalagmitestalactite

Stalagmitestalactite is not a standard scientific term; it is a portmanteau sometimes used to refer collectively to stalagmites and stalactites, the two principal cave formations produced by mineral deposition. In formal literature, the terms stalagmite and stalactite describe features that grow from the floor and hang from the ceiling, respectively. The two types are commonly found together in limestone caves and may, under suitable conditions, join to form a continuous column called a stalagnate or calcite pillar.

Both stalagmites and stalactites arise from the deposition of minerals, most commonly calcite, from dripping or seeping water. Groundwater carrying dissolved calcium carbonate enters a cave, and as it loses carbon dioxide to the cave air, calcite precipitates. Stalactites grow downward from the ceiling as water drips and leaves behind calcite; stalagmites grow upward from the floor as drips accumulate.

Growth is slow and influenced by drip rate, mineral concentration, temperature, humidity, and cave airflow. Stalactites can take on needle-like or pendant shapes, while stalagmites form rounded or conical mounds. When a stalagmite and stalactite meet, they can form a column that may span from floor to ceiling.

Etymology reflects their forms: stalactite derives from Greek stalaktos, “that which drips,” and stalagmite from stalagmos, “that which drops.” The combined term is rare in scientific writing; it is typically clearer to name the features separately as stalagmite and stalactite.