black spots, bright spots, no stains

Have the means used to reddish paving stones to remove smaller droplets waste oil, which loses occasionally my old truck. The remedy is fairly accurate and easy to spray, it develops in seconds, first a white dust. This white stuff I could despite copious amounts initially not get away - it remained a relatively conspicuous white spot. This stain faded but after some time and all kinds of downpours. Meanwhile, I can find no abnormality, the floor looks uniform, the white spot is gone and the oil too!