Tests of my red clay and Moon clay (Moon community, southeast Oklahoma) both of which were just rough processed through window screen. The sandstone revision 3 is the SS3 bar. It’s fine processed with some sand added back. The RC bar is reclaim. The reclaim is probably 85% local the rest are 100% local.
These are fired to cone 6. The moon clay and the red clay both have drying shrinkage of about 12%. However, I did bowls and small plates with both, and they all dried without cracking. The drying shrinkage is high but workable.
It may be interesting to see the final shrinkages on these since they are already quite high but the clays are not vitreous.
The one that surprises me the most is the sandstone clay. 7.5% fired porosity isn’t bad at all. I expected that one to be higher. I should be able to add 8-10% neph sye and be gtg at cone 6 and when I get my kiln conversion finished, fire high enough to have 100% local bodies.
| Drying Shrinkage % | Total Shrinkage % | Fired Porosity % | |
| Moon | 12 | 14 | 8.8 |
| Red | 12 | 15 | 13 |
| Sandstone | 9 | 15 | 7.5 |
| Reclaim | 10 | 14 | 1.5 |
