Partial-thickness burns (2nd degree burns)-- affect the top 2 layers of skin. Most notable by blisters (which may develop quickly or take 24 hours to form), but also red, mottled, wet and painful skin. Full-thickness burns (3rd degree burn)-- all three layers of skin affected; leathery, dry, charred, gray.
1 Discoveror: known since ancient times. 2  Place of discovery: not known. 3  Date of discovery: unknown. 4  Origin of name: from the Anglo-Saxon word  gold  (the origin of the symbol Au is the Latin word  aurum  meaning  gold ).
1 Mercury is a very rare element in the Earth's crust. 2  It accounts for only about only 0.08 parts per million (ppm). 3  Mercury generally is not allowed on aircraft because it combines so readily with aluminum, a metal that is common on aircraft. The modern element symbol for mercury is Hg, which is the symbol for another name for mercury: hydrargyrum. 2  Hydrargyrum comes from Greek words for water-silver (hydr-means water, argyros means silver). 3  Mercury is a very rare element in the Earth's crust. 4  It accounts for only about only 0.08 parts per million (ppm).