I saw Salman ibn Arammay within the worshops again. He has not ceased his toil over the perfection of his methods, this that he calls the 'cleansing' of metals. He has about him all manner of grotesque and strange materials he tells me is some kind of bronze or iron. Some ooze on the floor and others crunch underfoot as glass from the blowers' shops in Alexandria.
I must hope that this passion of his pays off, for he is a good man.

From the story of Salman the Cleanser, as told by his friend

Alchemy is all about transformation, purity and refinement. Of course, to purify and refine a thing you have to understand how it works, which is what advancing as an alchemist is all about: perfecting your understanding of the workings of animals, plants, people, and finally the soul itself.

The practice of Alchemy can take many forms. It is considered more of a Science than Magic by the Arabs of North Africa, and is more methodical and academic than its practice in the Easter Roman Empire. The laboratories in which an Alchemist might work can range from simple, disorganised shacks, to specially-built palaces of alchemical production.

Contrary to popular beliefs and the many jokes about Alchemists, they are rarely without eyebrows or in a state of some explosion. The requirements of Alchemy demand experimentation and eventual precision, but the determination to succeed counts for much.

It's in the nature of alchemical process that it doesn't scale up. It's not just a case of automating the production line so that you've got five people mixing the tears of a virgin into your gold dust; you need to make sure that each of those five people know the significance of mixing a virgin's tears in this way, that they've read and appreciated the Five Primary Texts arguing for and against the symbology of virgins' tears in the recipe, and that they've themselves personally undergone the experiences you've undergone to learn the recipe.

But you can make some small savings which will let you make quantities larger than the amount described here. To do this, you will need to spend extra AP on the recipe and have a healthy level of Administration. The end result still won't be quite as good as an alchemical production you've single-handedly made – time and effort and personal attention count for a lot in this discipline – but an army outfitted with True Steel armour (which, by the way, will take Bureaucracy 5 to pull off) will still have an edge over another army.

The Alchemist is capable of 'purifying' various objects, such as metals, liquids and so on. This has the effect of enhancing the effect and properties of that object, this can have the effect of also enhancing the less attractive qualities of the material. A more skilled alchemist (once you have learned a tier 2 spell) can all but eliminate some of the unfavourable qualities.

A common form of purification is performed on iron:

From the wood of a tree struck by lightning, iron ore that has been kept out of sunlight, the blood of a man who has killed, and snowmelt you can transform a thing made of metal into True Steel, a blue-grey metal that is light, hard, and keeps its edge indefinitely. It's very much in demand for weapons and armour. 2AP produces enough for one sword, one suit of armour, or any other similar quality.

From the yellow bile of a madman, sulphur mined at midday, tar taken from a tree grown in a mixture of three different earths, and the salt from a cat's tears you can make Alchemist's Fire, a strange liquid fire that can be stored within clay pots or glass jars, burns even without fuel, sticks to the things it touches, and doesn't go out unless doused with a large quantity of earth. Alchemist's Fire doesn't spread as effectively as regular fire does, but it is considerably nastier. 2AP produces enough to easily firebomb a building.

“The Water of Life, he claimed, would restore me to full health, but though I had some trust in him, I was yet amazed and surprised. My arms and legs were made as new, as if I had not been broken in that fateful war. It was much later that I came to understand that it had not been as miraculous as I had believed, for my right eye, that had been blinded in the same battle, had not been restored.” “Well dearie… we'll see if we can follow up that charlatan alchemist with a proven cure!”

-Captain Andronikos speaking to a witch of his experience with an alchemist.

“Have you been to see Gabn al-Azar? It is from him that I had bought those vials of powder two weeks ago. Remember? Yes, that which we inhaled. A good time was had, was it not? You should see al-Azar, he can get you anything you need.”

-A suggestion made to friend Mehmet.

“To turn one substance into another cannot be done. It is clear that there are many as have tried, but with much authority, I, John of Marsaille, can tell you it is impossible. I have studied at the foremost libraries of the Christian world, and I have observed the alchemists of Africa, and it is certain that lead cannot be turned into gold, or flour into salt!”

- The speech of John of Marsaille, known never to have left France.

“The Alchemist, Michaelos Pankratos, would not tell us what he had done and though he had been favoured by the Lord of Nicea, we have given him over to the Empress' authority, to pass judgement as she will. Yet it is clear that we saw those men age and wither in the merest of moments and apear as corpses, moving, yet dead. What this means for us all, I do not yet know, but will persever with this investigtion.”

- The notes of Eques Pompeios, an officer of the Byzantine government.