Coal forms from the accumulation of plant debris, usually in a swamp environment. When plant debris dies and falls into the swamp the standing water of the swamp protects it from decay. Swamp waters are usually deficient in oxygen, which would react with the plant debris and cause it to decay.
Porokeratosis is generally considered to be a benign condition though malignant transformation has been seen in all but the punctate variety, necessitating regular followup of patients with porokeratosis (Maubec et al., 2005; Sasson & Krain, 1996).
Pilaris keratosis is a skin condition that involves the formation of a protein in the skin that causes the formation of plugs that are hard and are found inside the follicles of the hair. This condition can actually justifiably categorized as being harmless since it does not aggravate with time.t is common among those who have got skin that is very dry. Pilaris keratosis is commonly known to run in families. Tiny bumps tend to appear on the skin for the cases that are not very severe. These bumps resemble goose bumps and are commonly found on the upper parts of the arm and the back part as well.