A close look at one of the "paved stones" - Sol 401

Caption NASA originale:"This picture from the MI on NASA's MER Opportunity is a mosaic of a target called "Gagarin" on a rock referred to as "Yuri." Opportunity brushed the target with the rock abrasion tool during the rover's 401st Sol, (March 10, 2005) and then took the individual images that are combined into this mosaic. The rock abrasion tool ground into the same target on the following Sol.
The circle from which the tool's wire brush has scoured dust off the rock surface is about 5 cm (approx. 2 inches) in diameter.
This rock is near the rim of "Vostok" Crater. Yuri Gagarin was the first man to orbit Earth. The Russian cosmonaut's spacecraft was named Vostok 1".
Nota: come vedete bene il Rock Abrasion Tool ha "lucidato", oltre alla pietra, anche alcuni Martian Berries. Nessun dubbio quindi: i 'frutti di bosco" di Meridiani Planum sono PARTE delle rocce. E quelli che vediamo al suolo? Sono essi "parte" del suolo o no? E se la risposta fosse "no" - come crediamo - che cosa potremmo dedurre?