The Chemistry of Paints and Painting is a free textbook on chemical aspects of painting. See the editorial for more information....

Mineral Lake

Synonyms: Mineral Lake, Pink-Colour, Potters' Pink, Laque Minérale, Minerallack

Attempts have been made to obtain mineral pigments of absolute permanence in order to acquire substitutes for the reds and purples of vegetable origin. None of them equals in intensity and splendour of colour the derivatives of madder. One of the best of these substitutes is mineral lake. This compound may be made in many ways. In some recipes stannic oxide, chalk and a little potassium chromate are directed to be heated together: in one process the operations are begun by precipitating a solution of neutral potassium chromate by means of a solution of stannic chloride. The precipitate is collected on a filter and thoroughly washed. Still moist, it is ground into a paste with half its bulk of pure nitre and some stannic oxide, and allowed to dry. The dry mixture is projected, little by little, into some nitre heated to low redness in a crucible. When the basic chromate of tin has settled, the nitre, still fused, is poured off. and the residue washed thoroughly with water. The product thus obtained requires calcination for two hours at a high temperature in a luted crucible, in order to develop its colour, which much resembles that of almond-blossom when the matter is finely ground.

It appears much richer in hue and less opaque when used as an oil-colour. It constitutes an unalterable pigment.

Under the name of Potters' Pink Mr. W. Burton, of Pilkington's Tile Works, has introduced to the notice of artists a ceramic pigment which is a variety of that which has been just described. He says of it that it was 'invented in Staffordshire by an unknown potter about a hundred years ago. It is obtained by calcining a mixture of oxide of tin and lime with a mere trace of oxide of chromium. It is a semi-opaque colour, unlike any usually supplied to artists. It should be particularly valuable in paintings in which it is undesirable to use madder or alizarin pigments.' It is scarcely necessary to add to this account that Potters' Pink is not only a permanent pigment which may be used in all methods of painting (including fresco), but that it is without action on other pigments.


Last Update: 2011-01-23