A stone on the moon (example)
A stone in general is a very typical example of a R0-reality. Therefore I chose my example situated at the moon with no people around to complicate things.
Now, from the perspective of an astronaut, the stone indeed belongs to the category R0: a stone among other stones without any particular relation between them. But this perspective is far from obvious! It is mentally constructed by us, conscious observers!
Without us the stone is only observed in our minds on Earth as a concept. So I would say it is primarily in exactly this conceptual way that this existency is distinguishable: 'something' made of quarks and leptons, like all the rest of the moons surface. From that perspective - a perspective adressing the whole of one particular reality as a single medium - its category of existence is actually R3 (for compare it to Stavenga's own example of the bubble-trail manifesting an elementary particle: again quarks and leptons - manifesting a stone)!
The disagreement is important to me as the different realities do not rule out each other: R0 is in this case embedded in R3 as 'something' expressed in the same material as all other things of reality.