The maner howe to prepare the stone Lapis la∣suli, and to calcine it whan you will grinde it.
TAke the said stone, that is to saie, that whiche hath the veines of Gold, and whiche hath ben in cimentes and fore saide profes, and breake him into pieces as bigge as Hasel nuttes, and washe theim in hote water, then putte theim into a Goldsmithes melting pot and sette it on the embers, and make theim redde hote and flaming, then take them out one after another, & quenche them in white Vinaigre distilled thorow a felt three or foure times, or els quēche them in the vrine or pisse of a yong child that is in health: And then distilled in the maner afore¦said: but note that Vinaigre is better, and make this calcination sixe or seuen times, for in stamping it, it will breake the better, and bee the easier to grinde: whereas if it were not well calcined a manne could skant stampe it, bicause it casteth it selfe within the Copper. But the other which can not endure the fire, and remaineth not in his proper colour beyng putte in cimentes, ye needs not so calcine thus, bicause it would lose all the meanes of his vertue and colour, and so shoulde you lose bothe your labour and your time.