Just for game balance and more of those things Ars Magica is usually not so concerned with:
I'd make spells that generate goods, produce about half as much in monetary value as the 'Touch of Midas' spell.
Salt is in fact gold/silver in those days, so I'd say you get as much value in salt as with the ToM for those 4 Vis.
Is salt a precious mineral, comparable to gold or gems?
Harvesting salt from the ocean: make players pay for this somehow. Covenants has guidelines on how much money magic items and rituals can bring. (I believe it's around 1 silver pound per Vis in an items and 5 silver pounds per Vis in ritual spells)
Using these guidelines will cause players to come up with stories that fit the local economy (like salt in Venice and Herring in Luebeck), wilst not creating free money.
This whole discussion is of course only relevant if money is an important part of the saga. (our covenant started out poor, making such issues important for our survival)
In point of fact, salt was also the commodity that cemented the power base of the Hanseatic League in the Baltic, so its just as vital a story seed there as in the Med.
In our saga, the salt-separating barrel only made it possible for us not to think about the economics of running a covenant and keeping track of all the mundane people, their needs and cravings much, much easier. When you have a decent supply of a product, your problems come with distributing it and selling it to your customers.
Instead of the trouble of being concerned about our well being financially, we got an extra story seed! Also, it gave us more time to focus on the laboratory work and occasional adventuring, and what more would a magus want. I know there are a lot of people who want to micromanage things, but for us, this worked out perfectly.
And yes, we started out poor as well, fighting to get a piece of something we could build our labs on, and even then we were cheated on the deal too many times. From wooden huts to stone houses, one custos per magus to a turb of grogs, the covenant used its seasons and became a stronger character in the play. And we didn't have to worry about the price of grain in a game that does not come with any price lists at all.
I think enter into the economic sistem of Venice is a good opportunity for a good Story to be telled (w/ forget the big Venetian hammer over our Covenant ) but now is a good idea to create a magic item for the creation of a small quantity of salt for our need, using the rules inside Covenant I suppose we could reduce some Covenant expense because we do not need to buy salt in the local market anymore.
I'm also italian and if you want communicate in italian with me via email: baldo.on.line@google.com .
I also ask apologize in advance to the english speaking sodales, I hope you don't come to the headache in trying to understand what I wrote.
Well, in the 13th century Venice no longer produced enough salt to meet the growing needs of Milan and the other inland cities, indeed the rivers gradually reduced the concentration of salt in the lagoon and many salt-works had cease their production.
The monopoly that Venice exercised not concern the production of salt, but its sale and distribution through a sort of public bank called the Chamber of Salt (in venetian Camera del Sal) and a very strictly regulated system of licenses.
The important thing was to ensure that the salt were traded only in and by Venice in order to impose its prices and perpetuate its role as a commercial hub in the Mediterranean and not to defend the insufficient local production, therefore Venice will be very happy to buy all the salt produced by a small island near there and then reselling it at higher prices to the cities of the Po valley!
There will be a bitter retaliation only if that small island will begin to sell directly its salt to the cities above-mentioned bypassing the Venetian monopoly.
Plugging into the Venetian monopoly is certainly a delicate operation but must take into account that much of the revenue of the republic derived from the sale of salt and that the salt market was not saturate (generally demand exceeded supply).
Of course your covenant must be careful not to sell too salt and not to unbalance the whole system, but given the large amount of salt traded by Venice I think there are still ample margins of earnings.
Perhaps the problems could come from other covenants of the roman tribunal, which have already thought to exploit the Venetian market and don't want that other troublesome hermetic competitors disturb the status quo.
Following a somewhat thorough treatment of the Venetian monopoly of salt:
Salt produced in the lagoon, the production were concentrated especially around the satellite town of Chioggia, was to be made available to the Chamber of Salt by law.
The nearby production centres, as Ravenna and Cervia, were forced by political and military pressure to sell all their salt to Venice.
To encourage the production centres far-away such Cyprus and Balearic Islands to sell their salt to Venice were established particularly beneficial prices.
The Chamber of Salt issued the licenses to exporters with instructions on how much, where, when and at what price to sell the salt thus acquired.
Finally, in the hope that it was not too prolix, for a saga set in the Adriatic Sea I heartily recommend the book "Venice, a maritime Republic" ("Storia di Venezia" in Italy) by Frederic Chapin Lane, you will find a plethora of information regarding history, society, economy and ships of Venice and the Mediterranean during the Middle Ages and the Renaissance.
Baldo, thank you very much for your clarifications about Venice's salt market. Moreover I find your suggested book very interesting, in my opinion a "must have" book
I think to sell my salt to Venice for a cheaper price, avarice could be very dangerous for my magus (and his Covenant)
Good to read such informed opinion on such a trade. It seems that you will have more problems in the magical arena than in the mundane arena because of the salt.
) but now is a good idea to create a magic item for the creation of a small quantity of salt for our need, using the rules inside Covenant I suppose we could reduce some Covenant expense because we do not need to buy salt in the local market anymore.