Pewter known as "trifling metal" or "trifle", was used for holloware and is made up of fine metal with approximately 4% lead. The last type of pewter, known as "lay" or "ley" metal, was used for items that were not in contact with food or drink. It consisted of tin with 15% lead. These three alloys were used with little variation until the 20th century. Older pewters with higher lead content are heavier, tarnish faster, and oxidation gives them a darker silver-gray color. Pewters containing lead are no longer used in items that will come in contact with the human body
Native metal brass, bronze, pewter, German silver, osmiridium, electrum, white gold, and silver-mercury and gold-mercury amalgam. Only gold, silver, copper and the platinum metals occur in nature in large amounts. Over geological time scales, very few metals can resist natural weathering processes like oxidation, which is why generally only the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isolated pockets where a natural chemical process reduces a common compound or ore of the metal, leaving the pure metal behind as small flakes or inclusions. Non-metallic elements occurring in the native state include