* Andesitic: The lava is composed primarily of andesite, a type of volcanic rock with an intermediate composition between basalt (mafic) and rhyolite (felsic).

* Viscous: This means the lava is thick and sticky, flowing slowly. This high viscosity is due to its relatively high silica content.

This type of lava is characteristic of stratovolcanoes, like Mount Pelée. The high viscosity contributes to the formation of steep slopes and the frequent explosive eruptions that have historically marked Mount Pelée.

Important Note: While Mount Pelée is known for its andesitic lava, it has also erupted other types of lava in the past, but andesite is the most common and associated with its famous eruptions.