Item #: SIOSWBK
Black Stoneware with Impalpable Grog. Sold in 27 pound boxes.
Black stoneware clay body with 40% impalpable grog (up to 80 Mesh). Formulated for artistic ceramics, it is ideal for wheel-throwing and modeling smooth pieces with fine details. The high content of grog confers an excellent behavior during drying and firing. Its beautiful and intense black firing color in oxidizing atmosphere is very exclusive of PRN range and becomes an ideal artistic mean of expression. In reducing atmosphere, metallic effects with shades of blue are obtained. Suitable for tableware (food-safe), according to ISO 6486:1999. Available in extruded body (moist form).
Firing range: Cone 5-6 (2205º-2269ºF)
Biscuit: Cone 06 (1855ºF)
Water content: 21%
Plasticity (IP Atterberg): 22
Carbonate content (CaCO3): 0%
Drying shrinkage: 7.0%
Firing shrinkage at Cone 6: 7.1%
Porosity (water absorption) at Cone 6: 1.3%
Dry bending strength: 4.6 N/mm2
Fired bending strength at Cone 6: 33.3 N/mm2
Thermal coefficient (a25-500ºC): 51.1x10-7ºC-1
SiO Item Code: PRNI