The Red Tincture The Red Rose the red blood of the Dragon
"He, then, who would prepare the incombustible sulphur of the Sages, must look for our sulphur in a substance in which it is incombustible -- which can only be after its body has been absorbed by the salt sea, and again rejected by it. Then it must be so exalted as to shine more brightly than all the stars of heaven, and in its essence it must have an abundance of blood, like the Pelican, which wounds its own breast, and, without any diminution of its strength, nourishes and rears up many young ones with its blood.
This Tincture is the Rose of our Masters, of purple hue, called also the red blood of the Dragon, or the purple cloak many times folded with which the Queen of Salvation is covered, and by which all metals are regenerated in colour."
- Basil Valentine, The Twelve Keys, Third Key
"By R. is signified the Root of our Work, and the Spring of continuing Radical Humours, which is our Red Tincture, and Red Rose which purifieth all in its kind."
- A Treatise of Mercury and the Philosophers Stone. by Sir George Ripley.