What color is a polar bear's fur?

The polar bear skin is black. The hairs are often called clear or transparent but are not truly transparent. They are also not white. They look white due to reflection. The hair of the fur contains keratin but no real pigment colors. Keratin is almost clear, but is off-white, the same as your fingernails, which are also composed of keratin. Viewed side-on, the polar bears' hairs appear colorless; viewed lengthwise (as if one were looking down a tube) the hairs no longer appear transparent.