Pure copper or high copper alloys are made from copper ore obtained from mines in the form of sulfides, which contain zinc, lead, and other sulfur. The ore is crushed and ground until it becomes a powder. A technique called flotation separates the metals from the non-metallic components of the powder. The next step is the concentration stage, which concentrates the minerals into a slurry containing about 15% copper. The copper is then melted and purified in several stages until it is 99% pure copper. At this point, it is cast as an anode. Oxygen is retained in the structure in the form of cuprous oxide (Cu2O). Most of the construction is pure copper. Copper metal solidifies from a liquid state through crystal growth. The crystals grow in preferred directions and form open tree-like structures called dendrites. A dendritic structure is typical for cast metals. A lower-melting mixture of pure copper and cuprous oxide called a eutectic, forms in the open spaces between dendrites. Eutectic particles are typically dark spheroids dispersed in a copper background. Cuprous oxide particles form a network that outlines dendritic cells. Porosity, seen as black spots in the microstructure, is also present in the as-cast material. Pure copper wire is a type of electrical conductor that is made entirely of copper, with no other metals or alloys added. It is known for its excellent electrical conductivity and corrosion resistance. Pure copper wire is commonly used in electrical applications where high conductivity and low resistance are important factors, such as in power transmission and distribution, building wiring, and electronic circuits. Additionally, pure copper wire is also used in the manufacturing of motors, generators, and transformers.