As of 0.63, stone textures can no longer be searched, and Small Stones spawn around the terrain of Chernarus. Two Small Stones must be combined to craft the Improvised Knife, instead of using one Small Stone on the ground texture.
As of 1.04, small stones are found on the nature paths and game trails.
As of 1.04, survivors no longer spawn with an Improvised Knife to prevent suicide to gain a more desirable spawn.