Have any of you gauntleted an apprentice in game yet?
We have in our saga three apprentices all due to gauntlet soon, one Bjornaer (already technically a magus by her masters standards as she has her heartbeast), a Flambeau (auram specialist), and a criamon (master is a necromancer).
When a magus is gauntleted to they need to be witnessed by a senior magus, such as a quaesitor? Or can a magus simple declare his apprentice a magus?
The various HoH books provide examples of gauntlets for each House. Bjornaer simply need to take their heartbeast form to pass their gauntlet; no senior witness is necessary but I suppose a curmudgeonly old magi could demand that a newbie change form before granting him a vote. I don't recall specific examples from the Criamon chapter but one assumes anyone able to sufficiently occult the meaning of their words would convince others he'd passed, so again I don't see the need for a witness. Criamon... um, my copy of that book is still en route, so I can't help there. I'd guess no, since the gauntlet is assumed to be a challenge and the parens is able to defend himself if the apprentice makes any false claims.
There are some groups that require senior witnesses, but I believe only the True Lineages do this as a rule.
From third edition :
"It used to be a popular way to Gauntlet an aprentice... Just drop him off somewhere far away and tell him to get to the Tribunal by his own means. Not only testing the aprentice, but also letting him/her enjoy the combination of power and not yet being entirely bound by the rules. This particular kind of gauntlet has however been frowned upon since an aprentice of house Flambeu burned down a hunting lodge that belonged to the archbishop of Canterbury..."
... quoted from memory since I actually gave my old 3rd ed books away when I got my 5th ed books.
WGRE has a nice Peripheral Code ruling (AA 1311 Iberia) that pretty much absolves apprentices during their gauntlet.
According to Hoh:TL (p.53) apprentices who pass their gauntlet then join the Order in "a formal ceremony". My guess is that a quaesitor must be present for this, as it would include swearing the Oath of Hermes. It isn't quite over for the apprentice even then, as he/she must now be taught the Parma (ArM5, p.32).
For the sake of convenience most tribunals probably have an annual "Ceremony of Welcome" at which apprentices can swear the Oath and magi who have immigrated from other tribunals can be recognised as residents. I think this has been explicitly stated somewhere in the rules, but I can't remember where.
I always thought the 'Formal Introduction' was at Tribunal...
Thanks to the excellent replies.
With all this in mind i suspect the following will happen in our saga.
The Bjornaer has technically already past her gauntlet so at the next tribunal she swears the code and is accepted as a full maga. She goes back to her parens for one more season to learn magic theory then thats it.
The Flambeau sets his apprentice a challenge, something to test her mettle (since our flambeau is a bit of a soft touch, this probably won't be terribly violent or dangerous). If she does alright, he declares her a maga and she swears the code at the next tribunal and is accepted as a full maga. She goes back to her parens for one more season to learn magic theory then thats it.
As for the criamon, weirdness is the rule of the day, but most likely some form of cryptic riddle game is the case, probably in some strange and mystically weird cave while under the influence of either magic or drugs to expand the mind. Then if successful its off to tribunal and blah blah blah.
This seems pretyt much appropriate. Thanks for the advice, i shall check the HoH books.
Found it on p. 123 of Hoh:TL, in the chapter on Tremere:
"By preference, the Gauntlet takes place in the presence of the exarch for the tribunal, a Quaesitor, and as many Tremere magi as are conveniently available. If a tribunal holds annual Ceremonies of Welcome, these are often used [emphasis added]."
That was certainly the case in 4e - in fact I think it was explicitly stated in the original Houses of Hermes book. The problem with restricting gauntlets to tribunals is that either apprentices have to wait until the next tribunal (which could be nearly seven years) or twelve magi of four covenants must be rustled up for the occasion. That may be problematic in a tribunal where covenants are far apart (e.g. Novgorod) or if the apprentice's parens is a maligned figure. An annual Ceremony of Welcome fixes the problem nicely.
Why is she going to use one more season to learn Magic Theory 
The final ting at new magus should learn is Parma, and after that be granted the title of magus.
After this title she should be a free magus in The Order Of Hermes, and not waste any more time with a parent.
'The Flambeau' is not a soft touch with anyone except his apprentice for whom he has developed something akin to fatherly love for. Don't be making Santiago sound like anything other than the pyschotic, violent nutcase that he is, now! 
Criamon gets asked a question, can't remember what it was, but no matter what they answer they pass the gauntlet.
Bonisagus gets a written test in MT.
Can't remember the rest, but I think they are mentioned in the houses of Hermes books...
Salvatore, our resident freaky Tytalos spent some time each day during all 15 years of his aprentices aprenticehood feeding the local sharks....
... for a gauntlet he bound his aprentice in iron-chains and locks and dumped him into the sea, smeared in cow-guts.
(The grogs were busy taking bets... ) So poor Jalinna lost a hand to the sharks and also losty any love for the man she had considered to be her father for most of her life.
Talk about a hard core gauntlet And I thought that dumping the apprentice in Siberia during February (he was from the Iberian tribunal) with a wooden staff and a linen tunic and telling him to be "where I (the pater) will be" in a week's time was harsh....
Xavi
I had a player whose mage was raised by a marched diabolist, and was travelling from Palestine to the Tytalus Domus Magnus in order to ask to take his gauntlet. The character had chthonic magic, vices, and lots of demonic lore and and the player played the guy as if he was very conflicted over which way to go, spiritually.
We played a few adventures, and I put him through a few tempting situations, where he could use his magic for the good of communities, or for personal gain. And he just kept riding the fence. Sometimes doing one, sometimes the other.
In the end, one of the other PC's ratted the apprentice out to a local quaesitor, on the grounds that the apprentice was a bad influence on the grogs.
The quaesitor got to the Tytalus Primus first. He charged the character to make the pilgrimage to Santiago de Compostella (from La Paz, across the Pyranees, and across northern Iberia) on his knees, without the use of magic. The quaesitor would hold an arcane connection to him as insurance.
The player / character accepted the demon's offer to get him out of the situation, and was never heard from again....