stickman wrote:Where are you getting those numbers from?
(160q bone ash + 2*(cave clay q10)+ 2*(feldspar q65)) / 5
= 62q clay NOT 84...
in order to get q 84 clay you would need q65ish cave clay instead of q10... which is basicaly impossible because i bet good cave clay spots are super rare.
I hate to break it to you but you're wrong, cave clay does not matter. The shortened down formula is 4*(feld)+(bone ash)/5 i tested this it is right.
This is why i find ainrans Q 97 kiln funny they had some Q80+ feldspars they would make a Q 97 kiln with Q 80 spars and Q 200 (bear bones) if they took more time to get some.

This was made with Q 10 cave clay Q 50-65 spars, i guess its your own choice not to believe me.