_Brown Stil de Grain_, _Citrine Lake_, or _Quercitron Lake_ is usually prepared from the berries of Avignon (ramnus infectorius), better known as French, Persian, or Turkey berries; but a more durable and quicker drying species is obtained from the quercitron bark. If produced from the former, it must be branded as fugitive, but if from the latter, it may be termed semi-stable. In either case it is a lake, precipitated from the alkaline decoction by means of alum, in such proportions that the alkali shall not be more than half saturated. The excess of soda or potash employed imparts a brown hue; but the lake being in general an orange broken by green, falls into the class of citrine colours, sometimes inclining to greenness, and sometimes towards the warmth of orange. It works well both in water and oil, in the latter of which it is of great depth and transparency, but its tints with white lead are very fugitive, and in thin glazing it does not stand: the berry variety dries badly. A fine rich colour, more beautiful than eligible, it is popular in landscape for foliage in foregrounds. Modified by admixture with burnt Sienna or gamboge, it yields a compound which, with the addition of a small quantity of indigo, gives a warm though not very durable green. In many of the Flemish pictures the foliage has become blue from the yellowish lake, with which the ultramarine was mixed, having faded. It has been remarked that the alteration made by time in semi-stable pigments is not so observable when they are employed in full body. Their use generally has been deprecated, but in shadows such vegetable colours as brown pink are sometimes of advantage, as they are transparent, lose part of their richness by the action of the air, and do not become black. Moreover, if mixed with pigments which have a tendency to darken, they mitigate it very much. This last, indeed, is the most legitimate purpose to which semi-stable pigments whose colour fades on exposure can be put. 224. MARS BROWN, or _Brun de Mars_, is either a natural or artificial ochre containing iron, or iron and manganese. Of much richness and strict permanence, it resembles raw umber in being a brown with a citrine cast, but is generally marked by a flush of orange which is not so observable in the latter pigment. 225. MIXED CITRINE.