Metal oxides in, or on the surface of, molten metal, or trapped in the casting.
An aluminum-laden scum that forms on top of molten aluminum.
worthless material that should be removed; "there were impurities in the water"
the scum formed by oxidation at the surface of molten metals
A scum formed on the surface of molten metal. Dross refers to the lead oxides, copper, antimony, and other elements that float to the top of the molten lead.
The scum that forms on the surface of molten metals.
Oxidized solder alloy and contamination laying on top of the molten solder in a wave soldering machine.
Oxide and other contaminants which form on the surface of molten solder.
Refuse or impurities such as whale blubber.
Metal oxides and other scum on the surface of molten metal or in a metal or alloy (mostly a non-ferrous term).
Dross is a mass of solid impurities floating on a molten metal bath. It appears usually on the melting of low melting point metals or alloys such as tin, lead, zinc or aluminium, or by oxidation of the metal(s). It can also consist of impurities such as paint leftovers.