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PB27

Prussian Blue is a synthetic organic pigment that was discovered by the paint maker Diesbach, apparently by accident, in Germany in the early eighteenth century. For many years, it was used not only as a colour in its own right, but also as a component of the original Hooker's Green. The other ingredient, gamboge, is highly fugitive, which is why many watercolours painted with Hooker's green have taken on a bluish tone with with age.  

It is a very transparent and heavily staining colour. It dries quite quickly in oil, and can therefore wrinkly if applied too quickly. It is suitable for use in oils, watercolour, and egg tempera. However, it shouldn't be used in conjunction with alkali substances, such as Lead White or Calcium Carbonate as it can turn brown, so it isn't suitable for fresco. For the same reason, it isn't used with acrylic resin binders due to their alkaline nature, so most paint manufacturers will replace Prussian Blue with a mixture of Phthalo Blue and black in their acrylic ranges. It requires a wetting agent to fully disperse into a binder.

Toxicity: B

PB33

Manganese Blue is an articficial mineral pigment, that is prepared by heating sodium sulphate, potassium permanganate and barium nitrate to 750-800 degrees Celcius. It has been produed as a pigment and as a colourant for cement since the 1930s, and is notable for its quick drying time in oils, its high transparency, and its bright, slightly greenish colour. Its weak tinting strength can cause it to be overwhelmed in mixtures, and it has a tendency to granulate as a watercolour. It is no longer used in commercial paints, but many manufacturers offer a Manganese Blue Hue, which is typically based upon Phthalocyanine Blue.   

Production of this pigment has now ceased, due to environmental and health concerns, therefore it is only available while stocks last.

Toxicity: C

Please note, unfortunately we are not able to send this product outside the UK.

PB15:3

Phthalo (Mona) Blue is a synthetic organic pigment, Copper Phthalocyanine, that has been in use since the 1930s. It has an extremely high tinting strength and is a staining colour, so cannot successfully be lifted in watercolour. It requires a wetting agent to fully disperse into a medium, and, when used at full strength, a copper sheen is visible in dried paint film. It is transparent, very lightfast, and has a medium-to-slow drying rate in oil.

Toxicity: C

While stocks last