Hi all, a lot of people release spreadsheets and what not to gauge potential profit when prospecting. I was browsing some websites and stumbled across this one:
Wow Prospector - World of Warcraft Prospecting Calculator
Simply input the price of ore and gems, and it will calculate profit. Nice if you don't have excel on your computer, or aren't allowed to download spreadsheets.
edit: Make sure to fill out ALL the prices or it won't work