ca: MANGANÈS, DIÒXID
Manganese dioxide is a dark brown metal oxide color with a trace of purple. It has always been used in the Majolica method, mainly for outlining and shading. It is a nicer color than black, softer, less industrial and this helps to give an antique look, but unfortunately it also creates more problems. It is a temperamental color which blisters easily, particularly on the outlines and can burn away and spread, but the most common failure is that although it seems to have the right consistency when painted, when fired it comes out weak and this undermines the strength of the design. Read more about: Blistering – Forming in pottery.