PT/CHF grogged terracotta 0-0.5mm 12.5kg

Terracotta (calcareous) earthenware clay with 25 % fine grog 0-0.5 mm (up to 35 Mesh). Ideal for medium size pieces. The presence of grog confers to the clay a very interesting textured surface (not flat) which, in turn, provides a set of suitable properties for the design of pieces in complex drying situations, thus avoiding the creation of deformations and cracks. Fired from 1040 ºC upward, it offers high resistance to frost and environmental degradation, making it ideal for pieces exposed outdoors (pots, tiles, roof tiles, etc.). Available in extruded body (moist form), being suitable for shaping and modelling.

Firing range*: 1020-1085 ºC / Cone 05½-04
Water content (throwing): 20 %
Plasticity (IP Atterberg): 15
Carbonate content (CaCO3): 17%
Drying shrinkage: 7.2 %
Firing shrinkage 1050ºC: 0.3 %
Porosity (water absorption at 1050ºC): 16.2%
Dry bending strength: 6.8 N/mm2
Fired bending strength 1050ºC: 23.6 N/mm2
Thermal coefficient 1050 ºC (25-500 ºC): 70.9x10^-7 ºC^-1

(*) Firing range recommended for the clay to develop its best performance, both in terms of technical and safety characteristics, under conventional firing conditions. The colour samples may show temperatures outside the recommended range to provide a broader view, but these are pieces fired under controlled conditions. Cone equivalence according to Orton table for self-supporting cones, regular-SSB and 150 ºC/hr heating rate.