Let's go with the dictionary one for starters: "the state of being aware of and responsive to one's surroundings.".

The rock is neither "aware" nor "responsive". It just stands there. It's a non-reactive set of minerals, lacking not just any capacity to react, but also life.

Though that's overthinking it. Sometimes you don't need decicated testing equipment to know something, just common sense.

Consciousness and responsiveness are orthogonal. Your dictionary would define the locked-in victims of apparently vegetative states as nonconscious. They are not.

Common sense is valuable, but it has a mixed scientific track record.

>Your dictionary would define the locked-in victims of apparently vegetative states as nonconscious

You can always find small exceptions to everything. But you know what I mean.

Except if your point is that, like the vegetative victims, the rock's brain is still alive.

Ackchyually, this is bigoted against all the electrons inside that rock. Subatomic particles deserve rights too! /s

Any definition for anything is tautologically true if you ignore exceptions