PRNF Black 4005: 12,5kg (Pick up at the studio only!)

Black sculpture clay with 40% grog 0,5 mm.
Formulated for artistic ceramics, it is ideal for large throwing and complex forms. Highly stable and versatile. Its beautiful and intense black firing colour in oxidising 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.

Firing range: 1200-1260ºC/ Cone 5-7
Biscuit temperature: 1000ºC
Water content: 21%
Plasticity (IP Atterberg): 22
Carbonate content (CaCO3): 0%
Drying shrinkage: 7.0%
Firing shrinkage (1260ºC): 3.6%
Porosity (water absorption at 1260ºC): 9.8%
Dry bending strength: 2.0 N/mm2
Fired bending strength (1260ºC): 22.0 N/mm2
Thermal coefficient (25-500ºC): 50.3×10^-7ºC^-1

Recommendations for use with glazes
Use zinc-free (Zn-free) glazes to prevent from unexpected reactions such as bubbling or color changes. Other elements that can react are zirconium (Zr) and tin (Sn). We recommend consulting your usual glaze supplier to ensure proper suitability with this ceramic clay body.