IF ANY INSOLUBLE MATTER IS PRESENT , OR IN CASE OF DOUBT , COMPLETELY EXTRACT THE FAT FROM THE FLASKS BY REPEATED WASHING WITH WARM LIGHT PETROLEUM , ALLOWING THE UNDISSOLVED MATERIAL TO SETTLE BEFORE EACH DECANTATION.
če je prisotna katera koli netopna snov, ali če smo v dvomih, popolnoma ekstrahiramo maščobi iz buč, tako da ponovno izpiramo s toplim petroletrom, ter pustimo, da se neraztopljeni material posede pred vsakim odlitjem.