, Size: 1 Kg, Particle Size Grades: Fine 20–45 µm

SKU: NAP-510-10GS1001K

In Stock

PRICE: US$ 10.75

The finest marble dust for making brilliant white grounds. Our whiting is dry ground from marble deposits in the United States. Dry grinding reduces it to a powder without destroying its particle structure, which is essential in making strong grounds and providing tooth on the surface of the grounds. The low surface area of our marble (when compared to precipitated chalk) keeps oil absorption low, which is ideal when adding it to paint and painting mediums. In painting grounds, it makes a durable surface with tooth for egg and casein tempera, distemper, encaustic, oil paint, and watercolors.

Both limestone and marble are calcium carbonate (CaCO3), which is also the composition of the mineral calcite. Marble is a metamorphic rock composed of recrystallized calcite. The metamorphism of limestone causes the calcite grains to grow in size and interlock with one another. The result is that marble is noticeably denser and harder than limestone. Limestone forms under deep marine conditions from the gradual accumulation of minute calcite plates (coccoliths) shed from micro-organisms called coccolithophores and hence contains invertebrate fossils. However, the metamorphic changes that convert limestone to marble almost always destroy these fossils.

Add marble dust to paint and mediums to create textural and bodying qualities without affecting the color. Marble dust has a little color in drying oils, so it can be added to oil paint without affecting the tint of the color.

Particle Size Grades

For a complete explanation of the available particle size grades and their use in artist's paints, please read .

Properties
Extender Pigment Marble, Ultra-Fine Marble, Extra-Fine Marble, Fine
Description A premium, ultra-fine particle size, wet ground marble with a closely controlled particle size distribution. NSF listed. An extra-fine particle-size marble with a closely controlled particle size distribution. It is the coarsest wet ground marble. Provides the lowest possible oil absorption. A fine particle-size marble featuring a careful control of oversized particles.
Chemical Analysis
Calcium Carbonate (CaO3) 95% 95% 98%
Silicon Dioxide (SiO2) 0.3%
Typical Physical Properties
Mean Particle Size 3 microns 11 microns 17 microns
Hegman Fineness 8 3
Brightness (Hunter Y) 96 92 92
Retained on 325 Mesh Screen 0.003% 0.1% 11%
Moisture 0.12% 0.12% 0.2%
Acid Insolubles 2% 2% 3%
Oil Absorption 9 g oil / 100 g pigment
Solid Density (lbs. gal) 22.7 22.7 11
Bulk Density, Packed 60 lbs./ft3 90 lbs./ft3 109.5 lbs./ft3
Bulk Density, Loose 40 lbs./ft3 65 lbs./ft3 51 lbs./ft3
Specific Gravity 2.7 2.7 2.7
Refractive Index, mean 1.6 1.6 1.6
Mohs Hardness 3 3 3

See other product variations