If you want and or capable of do panorama like "scans" of rocks stuff I could definitely try making textures out of them.
3 "mostly" equal in length panoramas making up a block allows plenty of texture to do a square at super high resolution, then stich, and use duplication brushes and painting to stich and hide repetitious parts, than down scale and crisp up with some sharpening if needed.
I use my phone which unfortunately seems to be upscaled or just has a blurry sensor which sucks for fine detail but I usually do 3 4k panoramas and then stitch them together, fix some problem areas, then I make it seamless and do the above stuff I mentioned. There is a plugin for photoshop I use called Seamless Texture Generator. Great start but definitely needs manual love afterwards..