When discussing the value of the gold, Vitti says: "$350 an ounce, 16 ounces to the pound, 90 pounds to the bar." Precious metals are measured in Troy weight in which there are twelve ounces per pound not sixteen as in the Avoirdupois system.
In the scene where Paul Vitti is working in the jewelry store, the last shot shows Paul wearing a yarmulke as he turns away from the camera. However, he is clearly not wearing the yarmulke in previous shots when the back of his head is visible.
The gold stolen is said to be worth more than $22 million as they are 90lb bars. However, the bars clearly do not weigh that much. They appear to be the standard gold bar size which is 400oz (or 25lb) with dimensions of approx 8" x 3" x 2". Also, the bars depicted are marked only "24K" whereas real bars would have serial numbers on them. (Additionally, if the bars really were 90lb each, they would not be able to be piled up in the back of the van without causing damage - they would weigh more than two tons)