Muse Developments was chosen to deliver the new Â£107m look for the site of the former council headquarters.
The plan is for offices, restaurants and a hotel.
BBC Scotland revealed last month the building specifics had not been finalised, but Muse has now confirmed the breakdown.
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Aberdeen City Council said it had reached an agreement in principle with the developers in terms of the details of finishes and materials, and a final formal submission was expected shortly.
The specification of building materials should have been agreed before work started. However, Aberdeen City Council agreed to give some leeway.
New images of how the project is expected to look have been released.
Muse said businesses including All Bar One and Burger and Lobster have agreed to take restaurant space.
And Marriott is set to operate the 126-bedroom.
Muse regional director for Scotland, Stephen Turner, said: "Marischal Square will be a keystone of the vision of the council's city centre masterplan proposals."
In 2011, more than 1,000 council staff vacated the 14-storey St Nicholas House building, erected in 1968, for the newly-refurbished Marischal College building.
Two-thirds of the outside of the Marischal Square development in Aberdeen is set to be glass with the rest made of granite.