Scientists say their best chance of determining whether Mars ever hosted life is to study its surface materials in sophisticated home laboratories.
The scientists want to determine whether these Paver Stones are sedimentary or volcanic in origin. Either is interesting, but the special quality of volcanic rocks is that they can be dated with very high precision and accuracy in a lab, says chief scientist Ken Farley.
Perseverance will first abrade the surface of a chosen section of Paver Stone, to remove Mars' obscuring dust, and then examine the site with its powerful instruments.
These are held on the end of its robotic arm. They are capable of determining the chemical composition, the mineralogy and texture within a rock - to identify it definitively.
The rover will be caching something like 40 of these small sample tubes over the course of its mission. Later projects from Nasa and the European Space Agency (ESA) will arrive on Mars to take ownership and bring them home.