# Mineral Hardness Color Transparency Crystal System Probability See More
1Montmorillonite1.0 - 2.0White, buff, yellow, green, rarely pale pink to redTranslucentMonoclinic0.015
2Pyrophyllite1.0 - 2.0White, gray, pale blue, pale green, pale yellow, brownish greenTranslucent, OpaqueTriclinic0.006
4Sylvite1.5 - 2.0Colourless, grey, white, yellowish to reddish, seldom blue or violetTransparent, TranslucentIsometric0.004
5Gypsum2.0Colourless to white, often tinged other hues due to impurities, colourless in transmitted light..Transparent, Translucent, OpaqueMonoclinic0.003
6Sepiolite2.0White, light gray or light yellow.Translucent, OpaqueOrthorhombic0.003
7Palygorskite2.0 - 2.5White. grayish, yellowish, gray-greenTranslucentMonoclinic0.002
8Vantasselite2.0 - 2.5WhiteOrthorhombic0.002