089r - - - - - Sand of burnt oxen bone and rock salt
I pulverised them separately & finely ground them on porphyry, as much as I could. Then I mixed as much of one as the other & reworked them on porphyry. Next I moistened it in paper, folded in a wet napkin, which is made faster than in the serain of the night or in the moisture of the cellar. And I have not found anything else which releases more neatly than this one. It wants to be rather humid. And if you want to cast very thin, make sure it is very hot. It came out very neatly in soft tin, like the first one, and withstood several casts. For tin, I believe that it is not necessary to seek a better one, nor for fine lead also, which comes out almost as neatly as tin. Tou the bone of the foot of oxen is always so lean on its own that, without being mixed with one or two parts of some fat sand &having bond such as tripoli, salts, felt, ashes & similar things, it would not release, & would not mold neatly for it crumbles.
Reheating or drying a molded frame
Always put the most delicate part, such as the face, above, so that nothing falls in it that could hinder your fusion.
Natural sand
It does not want to be reheated for lead and tin, m and is better very new & fresh.