There was no South America, no North America, no Africa — the continents as we know them had not yet been carved by the plate tectonic movements that have operated continuously since.

Multicellular life had barely emerged; most of the life on Earth at that time consisted of single-celled organisms, bacteria, and archaea.

The world in which these rocks were deposited was so different from the present world that it is effectively alien — not just historically distant but fundamentally different in its atmosphere (much less oxygen), its ocean chemistry, its biology, and its geography.

And yet the rocks from that world are sitting in the sun on the summit of Roraima today, being walked on by trekkers from Brazil and Germany and Japan, being grown on by carnivorous plants, being used as hunting ground by Roraima bush toads, being rained on by the constant cloud cover that characterizes the summit climate.