"Carmine," made from the cochineal insect, is the most brilliant red pigment known; but too expensive for ordinary house painting, and not durable; sometimes used for internal decoration. "Hod-lead" ground by itself in oil or varnish forms a durable pigment, or it may be mixed with ochres; white-lead and metallic suits generally destroy its colour. "Vermilion" is mercury sulphide found in a natural state; best comes from China; artificial vermilion is also made both in China and on the Continent from a mixture of sulpbur and mercury; genuine is very durable, but it is sometimes adulterated with red-lead, etc., and then will not weather; on heating some in a test tube it should entirely volatilize, and the powder crushed between sheets of paper should not change colour. German vermilion is antimony tersulphide and of orange-red colour "Indian red" is a ground haematite ore brought from Bengal, sometimes artificially made by calcining iron sulphate; tints vary, but a rosy hue is considered the best; may be used with turpentine and a little varnish to produce a dull surface, drying rapidly, 01 with boiled oil and a little driers, in which case a glossy surface will be produced, drying more slowly. "Chinese red" and "Persian red" are lead chromates, produced by boiling white-lead with a solution of potash bichromate; the tint of Persian red is obtained by the employment of sulphuric acid; these are much used for painting pillar post boxes "Light red" is a burnt ochre, and shares the characteristics of raw ochres already described. "Venetian red" is obtained by heating iron sulphate produced as a waste product at tin and copper works; is often adulterated by mixing lime sulphate with it during the manufacture; when pure it is known as "bright red"; when special tints of purple and brown are required, these should be obtained in the process of manufacture, and not produced by mixing together a variety of different shades of colour; when the tint desired is attempted to be obtained by this latter course it is never so good, and the pigments produced are known as "faced colours" and are of inferior value. "Rose pink" is a chalk or whiting stained with a tincture of Brazil wood; fades very quickly, but is used for paperhangings, common distemper, and for staining cheap furniture. "Dutch pink" is a similar substance made from quercitron bark.