At first glance, rocks seem to be nothing more than chunks of planetary matter whose molecules have crystallized into rigid structures. They also seem to be relatively permanent, inanimate features on the landscape. Having observed the rocks in my yard for over ten years, though, I've noticed that they're by no means permanent. After several months, they dig little pockets for themselves themselves to rest in, and each year they slowly sink deeper into the pockets until they entirely disappear from view.
I've also observed a tendency of rocks to drift to new positions in the yard, especially after a severe storm.
Both the sinking and the drifting occur with the help of water, wind, and plant life. The water softens the earth, allowing the rocks to sink under their own weight. The wind buffets the rocks, perhaps moving them a few feet, especially if there is a heavy rain creating rivulets of water to further propel them. Vines grow up around the rocks, pulling them toward the earth.
It's probable that much of this activity is the result of random interactions between elements. However, sometimes the interactions between water, wind, plant life, and rocks seem to be a dance, inspired by the nature of the participants.
Rocks are among the oldest structures on earth, and are composed of hard elements and compounds, including silicon. Silicon is an excellent recorder and storer of information. Many rocks have been in existence for billions of years, and if they are able to record as well as I think they are, they will have stored a vast amount of information during that time. I believe that given enough time and enough information, anything can achieve sentience.
Rocks do not all have the same feel. To me, some feel "sentient" (not in the sense we understand sentience) and some do not. The ones with the sentient feel may be quite plain on the outside, or they may have intricately irregular surfaces that are twisted into interesting shapes.
Occasionally, I encounter rocks that appear to have faces, most of which feel quite sentient. Usually, a rock will have more than one face -- they've had enough time to develop many personalities, after all. The image below is a rock on the surface of Mars, which has remained undisturbed long enough to develop a rather interesting personality...

Whether these faces reflect the internal personality of the rock by some intentional dance between the rock and other elements, or if they are just the chance result of eons of erosion, is hard to say. Whatever the answer may be, I've kept a few of them with me for many years. One in particular (a little pinkish-white rock), has multiple faces. On one side, it's angry/scary but winking at the same time. On one side, it's sad. And in profile, it's laughing. I call it my laughing rock.
To the left is a picture of a bigger rock with many faces (not someone I know)... These rocks seem rather curmudgeonly, but then, what would one expect from someone over a billion years old.
The faces probably do not reflect any emotion I am familiar with, though, because a rock is not a warm-blooded, mobile, mortal creature with mammalian emotions. It is just a very, very old aggregate. On the other hand, they're born of the same earth that we are, so maybe there's more of a similarity than I'd initially suspect. Many of the rocks with faces come from the banks of the tiny creeks running through Maryland's wild places. Perhaps the water and the rock danced together to reflect the endless cycles of light, dark, and water that the rock "saw" for billions of years. Whenever I am in a wild place, I am the most fascinated by the deposits of rocks by the creek beds, where the rocks with faces like to dance with the water...
Some people believe that these are "Spirit Stones" (that nature spirits inhabit them). Maybe... But I think it's the intelligence of the rock itself, which is the intelligence of the earth. After thousands of years of information gathering, a rock may sink back to the earth's crust and return to the larger aggregate.
But before it does that, it may smile, frown, wink, or laugh in the direction of those who chance to see it...