One of the distinctive features of the Roraima summit landscape is the abundance of quartz — specifically, quartzite, which is sandstone that has been metamorphosed under heat and pressure into a harder, more crystalline form.

Quartz is one of the most chemically resistant minerals that commonly occurs in Earth’s crust.

It does not dissolve easily in water.

It does not react readily with the acids produced by organic decay.

It does not break down quickly under the physical stresses of weathering.

This resistance is part of why the Roraima Supergroup sandstones have survived at all — the quartz-rich rock resists erosion better than most sedimentary formations would.

But the same resistance that preserves the rock creates difficulties for life.