This is a sebaceous cyst on forehead, sebaceous cyst usually forms from swollen follicles which may be initiated by trauma to skin, certain cells are formed inside follicles which start secreting keratin a kind of protein. Cysts are drained or excised, here you can see the keratin coming out of cyst in coiling form. Do you know? Some of African Antelopes have horns made of keratin, keratin production also take place in process known as cornification. Keratin repels the water off from skin making it water proof. Do you know? Spiders also form keratin in form of silk fibroins. Around 20 types of keratins are found in human body. Sebaceous cysts are not comedone (ie black & white heads). Structure of keratin is similar to a helix type.