For sake of the matter, I don't go out in the sun without shoes, and I'm Caucasian from Russian decent so, I'm a white guy no doubt about it. There no pain associated with this condition. The discolouration is mainly on the top of my feet and around my ankles. My toes, sides of my feet and the underside portion of my feet are "normal" and not of concern. I have my own speculation regarding this quite noticeable feature that resembles "dirty feet:" I am 34 yrs old. I have and do currently work in the construction trade as a "handyman." About 5 years ago I started the habit of wearing my leather work boots to work without wearing socks. Mind you I had two sets of work boots, both a tan colored soft leather type; inevitably wearing them out. So I figure that the marks on my feet are either the staining caused by the leather boots rubbing and wearing into my skin maybe the tannins found in leather, OR that my skin was damaged from the harshness of the boot material rubbing constantly on the very thin and delicate tops of my feet and ankles. that the discolouration maybe the staining from broken blood vessels long since past. the color is permanent and doesn't fluctuate, like birthmarks on my feet type thing. btw I wear socks now. thanks. any ideas?