An Introduction to Mineral Fillers for Paints & Coatings - Vanderbilt .Mohs Hardness Scale. 1. Talc. 2. Gypsum. 3. Calcite. 4. Fluorite. 5. Apatite. 6. Feldspar. 7. Quartz . Dry brightness and color-in-oil of a mineral will affect how the.determination method of brightness of talcum,Physical Properties of Wollastonite - ImerysThe dry brightness and whiteness of wollastonite are important in determining it's suitability for certain filler and . The Hunter method is also used to measure the brightness of wollastonite. . the hardness of talc is 1.0-1.5 and calcite is 3.0.
determination method of brightness of talcum