would loose color if they were not ground properly.
             Strongest colors were the most popular. Deep blue ultramarine, lapis lazuli and brilliant scarlet vermilion set against a gilded background had a lot of appeal for the time. Opaque yellow and red lead were also popular manufactured colors. Looking back one can understand the pallet of late 14th century Tempera paintings based on what pigments were available. Pigments would be imported from all over Europe, they were natural minerals and earthy deposits that could only be found in certain parts the land. Then there were synthetic paints, created with chemical equivalents of mineral materials. Lastly there were paints taken from animal or plant sources.
             The Tempera painting process was unique. The paint would be applied to the piece with fine brushes made with hairs of a minever or ermine, a member of the weasel family. The hair was bunched together and tied into quills. Larger hog bristle brushes were made in the same fashion. The water added to the pigments and the overall process of dry
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