3#-7# suitable for wall paint and tempera(scenery)
9#-11#suitable for wall paint and tempera (figure)
13#-15#suitable for making watercolors
The "Ultramarine" color in natural painting is not blue copper, but the color of lapis lazuli. Blue copper is "stone green". The grade of lapis lazuli is usually divided by 3A, 4A, 5A, 6A, 7A..., the higher the number, the higher the ore level represents. At present, most lapis lazuli brands still use the old and clumsy "Chinini purification method," which makes lapis only available in 6A and 7A levels and 3A is synonymous with "dirty paint."Now Shanqu has broken this concept and purified the ordinary 3A lapis lazuli to the extreme, making the pigment as pure as fat.
