Wonderful rock but how large is one rock compared to the player and is it possible to see a wire frame render? Just looking at the silhouette, I get the vibe that the geo can be cleaned up a bit to reduce to polycount
It's a very good model, and the texturing is well done. But, it's high poly for a rock, unless this rock happens to be a big feature of the game that the player spends a lot of time looking at. It's formation looks strange, almost as though it was a group a rocks attached with cement.
Rocks happen when a chunk of stone is broken off a larger stone or mountain. Sometimes they are cut by glaciers, sometimes freezing rain breaks them, sometimes the path of water or wind can do it too. They weather in particular patterns according to the environment. Rocks the are broken by the effects of rain and ice have flat, angular surfaces. Rocks that are washed by the sea or river have smooth, rounded surfaces. Rocks cut by the wind have sculptured forms.
This seems to be a combination of things. My best guess would be that its quite a soft stone and it landed under a mini waterfall at some point. Probably from somewhere tropical. Although I'm not an expert, I do spend a lot of time around rocks and mountains.
I doubt most people will think about it in that much detail. Unless the player lives somewhere rural and mountainous, this will fit with most people's concept of what a rock looks like. The poly count is good in that case, using the polys where people are going to see them.