If a weapon or effect, or any call strikes you while you are casting, then your casting is interrupted and you must start the vocal over, but do not lose any magic or spirit. The only exception to this is if the call is, precisely, "NOTHING". This is very strict, so a RED NOTHING will interrupt anyone, even a pyrokin, as it is not a "NOTHING" - the reason being that even that effect is distracting enough to break your concentration. This means you are interrupted in all other situations, for example if you DAC a blow, or you have magical armour. You are not mechanically interrupted when someone distracts you, say, by throwing a bucket of water over you, however you should feel free to roleplay losing the spell or miracle and starting over.
Source: Rules clarifications
Also note the spell research page has been nuked as it was a duplication of this paragraph.
There are many spells available in the libraries of the Colleges that are not on the teaching syllabus. If, in general, you want to learn a spell and you can't find it on your colour's spell list, it can be found in the College library. The mechanic for nonstandard spells is easy:
You submit in your downtime the 'new' spell you wish to learn. If it is available in the College library then you will get the reply "You can find and learn this spell. There is a charge of N shillings to cover laboratory and book costs." Costs will typically be on the order of 5 Shillings per spell level. If the spell you want is not available, or you are trying for an entirely new effect, then it is possible to research new spells yourself. You will get the reply "This spell is not in the library. If you start research on this effect, you can expect to get [description of spell] with a week's work." If that was not the spell you wanted, you can continue to negotiate (this process simulating the weeks of research you are undertaking to get your new spell) or give up and try another spell. There will be a nominal cost for lab use, not exceeding 10 Shillings per week of research plus 5 per spell level when you wish to learn the spell. In general, the first of the two answers is the most likely. The Colleges have vast libraries; if a feasible spell is not in there, there is usually a reason why not.
You can ask what's in the library and you will get a sample list, this represents the most well known spells in the library. (e.g. it is well known to apprentices that the grey spell: Buzby's insulting gesture is in the book "101 other uses for Buzby's hand spells"). Learning a non-syllabus spell from the library takes 1 week.
Other spells can be researched, research will usually take 2 weeks, and requires lab access. The mage may get lucky during their research and find that the spell actually exists in the library, but wasn't on the general reading list (Spells that are solely system calls that a given colour of magic is good at have a good chance to be discovered this way). In such a cases they manage to learn the spell after 1 week. It is also possible that in addition to the end result of the research, after 1 week the mage will have a partially completed / work in progress spell of limited utility/has serious drawbacks. You may purchase this spell with XP if you wish.
The metal allowance for a mage is measured in daggers (this is used both in an out of character for convenience). The maximum a metal a mage can safely carry is "3 daggers worth" of metal, thus they could carry with daggers with them with no adverse effects, but any more will trigger discharge.
Common metal amounts:
Some of these contain the phrase "regardless of pysrep", these are usually things that can contain some metal, and thus a specific amount has been defined. Please do not take the piss by using an all metallic pysrep.
Arcane connections decay over time. Personal possessions last a week, hair maybe two weeks, blood a month or so and a severed limb/spirit weapon about a year.