Here's a way to create a decorative textured finish for a cement surface. Once your cement is poured and flowed out, evenly cast granite chips across the wet surface. Gently bury the stone into the concrete with a bull float. Let this set for four to five hours, then rinse with a light mist of water. Finally, brush the surface lightly with a soft broom; this will expose the granite to give the installation a look of stone.
For more on cement, consider:
Should You Consider a Concrete House?
Concrete and Cement: A Case of Mistaken Identities
Cement Your Place in DIY History with These 9 Easy Concrete Projects