Benjamin Wegner
Videos
Page
Jacob Benjamin Wegner was a Norwegian business magnate, estate owner and timber merchant.
Benjamin Wegner
His wife Henriette Seyler (1805–75), daughter of Berenberg Bank co-owner L.E. Seyler, drawn by her sister Molly in 1827
Cobalt blue, made from cobalt, a precious metal that was more expensive than silver
Blaafarveværket
Cobalt blue
Videos
Page
Cobalt blue is a blue pigment made by sintering cobalt(II) oxide with aluminum(III) oxide (alumina) at 1200 °C. Chemically, cobalt blue pigment is cobalt(II) oxide-aluminium oxide, or cobalt(II) aluminate, CoAl2O4. Cobalt blue is lighter and less intense than the (iron-cyanide based) pigment Prussian blue. It is extremely stable and historically has been used as a coloring agent in ceramics (especially Chinese porcelain), jewelry, and paint. Transparent glasses are tinted with the silica-based cobalt pigment "smalt".
A sample of a commercial cobalt blue pigment
Pierre-Auguste Renoir, Boating on the Seine (La Yole), c. 1879