Orton | LRB09
Large Regular Pyrometric Cone 09
Cone 09 in Orton's large regular series, the witness cone that stands on the kiln shelf beside the ware. Its bend after the firing shows whether the kiln reached, missed or passed cone 09, which a controller reading on its own cannot tell you.
$35
Suggested retail price. In-store prices and availability may vary by location.
This is Cone 09 in Orton's large regular LRB series, the standard witness cone for the kiln shelf. Orton lists it bending at 917°C (1683°F) when the last 100°C of the firing climbs at 60°C an hour, and at 928°C (1702°F) at 150°C an hour. A cone responds to time and temperature together, not temperature alone, so the number it bends at depends on how fast the kiln is climbing. Orton lists cones in this part of the range for craft and art bodies, wall tile, glazes and some structural clay. Cones 010 through 3 are red iron bearing and can come out matte, green or bloated if the kiln is short of oxygen, so Orton recommends the Iron Free series for reduction firing. The cone does not stand on its own. Set it in a cone plaque, clay pat or wire holder with 51 mm (2 in) showing above the mount and leaning at 8 degrees. If that height is out by 6 mm (¼ in) the bend shifts by more than half a cone.
- Cone 09
- Bends 917°C (1683°F) at 60°C an hour
- Bends 928°C (1702°F) at 150°C an hour
- 63.5 mm (2½ in) tall
- Mounts in a cone plaque, clay pat or wire holder
- 51 mm (2 in) exposed, leaning at 8 degrees
- Finished at a 90 degree bend
- Red iron bearing, use the Iron Free series for reduction
Downloads
Orton’s cone charts and guide to cones and firing.
