What is Copper Hydroxide? What's the difference between Copper hydroxide and copper carbonate? What is Patina

Cu(OH)₂ 

Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is a strong base, although its low solubility in water makes this hard to observe directly.

Copper(II) hydroxide has been known to man since copper smelting began around 5000 BCE although the alchemists were probably the first to manufacture it. This was easily done by mixing solutions of lye and blue vitriol, both chemicals which were known in antiquity. 

It was produced on an industrial scale during the 17th and 18th centuries for use in pigments such as blue verditer and Bremen green. These pigments were used in ceramics and painting.

This is the patina that forms on bronze and other copper alloy statues such as the Statue of Liberty.

Don't mix with Copper(I) hydroxide. It is unstable and readily oxidizes to form copper(II) compounds, particularly copper(II) oxide (CuO).

Copper Hydroxide - Uses in Pottery

Such products include Kocide 3000, produced by Kocide L.L.C. Copper(II) hydroxide is also occasionally used as a ceramic colorant. Metallic-based materials impart fired color to glazes and bodies.

Formula: Cu(OH)₂
Molecular Weight: 97.561 g/mol
Form: Blue-green powder
CAS Number: 20427-59-2
Density: 3.368 g/cm³
Synonyms: Copper(II) hydroxide, Copper dihydroxide, Parasol, Champ, Cuzin, Kocide, Wetcol, Cupravit blue, Blue Shield, Cupric Hydroxide