Bit late to put the explanation and I'm not happy! Like Areop-Enap I would not of bought the island if I knew it was going to mess up my granite masons which are down south. I don't want to build another up north to work the deposits which are wider apart than the ones down south, its less efficient, which maybe ok for some but not for me. If I can not block that new deposit I want the amount increased by one so I don't loose out twice ( Gems and poorer granite production ) That would not be fair especially as the reasoning behind it is released after the fact.
I already said in my previous post, having alternate sites for mined deposits is fine once their location has been determined as the player can place the store where it is most appropriate. Remember a store is both cheap to build and left at level one without effecting ore production. Masons are completely different, especially granite masons which are far from cheap and require leveling up which is also not cheap.
And before some Dev starts to argue that having an extra granite deposit would un-balance the game, as if they have a solid grasp of that word, I would suggest a simple buff solution which when applied to a granite deposit turns it into an extra marble one ( or stone if you must ) instead thus blocking the unwanted site and allowing the search to find granite on the previous site before new island upgrade.
ps. The granite deposit I have lost is the one closest to a mason and the reserve is the furthest from any of my other masons, so I am really miffed. How to turn a positive upgrade into a negative one, do you go somewhere to learn how to do this ?