Hi, away from books, so can anyone tell me how much does a pawn of vis cost in terms of silver pounds?
Thx 
Ten pounds then. Thanks
Most covenants won't be selling lots of vis for silver. Probably only to cover shortfalls, and then they will try to get the best price. Also note the vary widely thing. There is no set price. Ten pounds is probably a rough starting price, assuming there are no nearby truly rich covenants, but if you want to buy lots of vis the prices will start to go up. If there are nearby rich covenants they'll probably out price you for that vis. If they have a 500 pound surplus they'll probably pay 20-30 at least per pawn.
Don't forget that you can get Vis loans from your local Mercere House at a rather reasonable interest rate...
I needed the value for a flambeau trying to hire a band of mercenaries that contains hedge spellscasters (that are aware of the OoH). 10 pounds to a pawn works as a rough estimate to make calculations here
Xavi
The Andorra sga uses a base exchange rate of 1 pawn Vim equals 12 pounds silver. The base exchange rate for magi in most of the Order is 10 pounds per pawn. It isn't that vis is at all scarce, it is just that silver is more plentiful (and 12 is easier to divide by 4). For selling vis or vis-equivalent items to mundanes (or anyone outside the Order), the price is 15 pounds per pawn. If we were to buy vis from a mundane, I am thinking no more than 8 pounds per pawn.
And yes, if you take Roberto's offer in vis instead of silver, you are getting a bum deal. His thinking (and mine) is that he doesn't want to spend too much vis (or cash), as it will make the chapterhouse unprofitable.
10 pounds/pawn is very rough, and there are so many other factors at stake that I would use any scenario involving vis-for-coin as a story hook - because there are many factors that can upset the exchange rate.
I'd look at how much mundane wealth the player covenant has and decide from there if you want to simply make the exchange simple or want it to be a 'last resort' move. 10 pounds/pawn is 10% of a typical covenant income per pawn. If the covenant is rolling in coin and everyone knows it, the price per pawn may be as much as 100 pounds/pawn. After all, the seller probably knows who they are selling to and there's no vis-merchant's guild to control prices.
Also, if everyone knows that you're able to use that vis to make wealth (and the Tribunal hasn't plugged whatever loophole you're abusing yet), that's likely to inflate prices a bit.
If you can get away with it, pay 'em in salt.
To be fair, it'll be ~10 metric tons (or 20 tons. I forget the exact math) of salt for that amount of silver, but still. That's actually just over one lvl 4 PeAq "dry out salt water" spell. (~8900 kg of salt per casting.) Of course, that's a story in and of itself, I guess...
I am interested because my character is the one that is supposed to be paid, so no, I am not interested in salt 
And IIRC salt was a state (big fish in the pond) monopoly, so I guess it is not that easy to get away with that.
In that case, the value of a pawn is 200 pounds (gold trades 1:10 for silver, I think?), minus the expenses of getting a CrTe 20 ritual and making sure the quaesitores look the other way. : )
If you're the seller, the price is as much as you think you can get away with and how desperate the buyer is.
Value in real life is a really interesting thing precisely because it is so dependent on a variety of external factors.