Gold and Diamonds

Another area division puzzle, one of my most recent inventions. Rules below:

Divide the grid along the gridlines into gold and diamond mines - connected areas of at least 2 cells - so that each gold mine encloses exactly one shaded square and one unshaded square, and each diamond mine encloses one diamond. Gold mines cannot enclose any 2x2 groups of cells, but diamond mines must enclose at least one such group of cells. Every cell in the grid must belong to either a gold or a diamond mine.